The Oyo Empire was a Yoruba empire of what is today western and northern Nigeria. Established in the 14th century, the Oyo Empire grew to become one of the largest West African states encountered by pre-colonial explorers. It rose through the outstanding organizational skills of the Yoruba, wealth gained from trade and its powerful cavalry. The Oyo Empire was the most politically important state in the region from the mid-17th to the late 18th century, holding sway not only over most of the other kingdoms in Yorubaland, but also over nearby African states, notably the Fon Kingdom of Dahomey in the contemporary republic of Benin to the west.
The mythical origins of the Oyo Empire lie with Oranyan (also known as Oranmiyan), the second prince of the Yoruba Kingdom of Ile-Ife (Ife). Oranyan made an agreement with his brother to launch a punitive raid on their northern neighbors for insulting their father Oba (King) Oduduwa, the first Ooni of Ife. On the way to the battle, the brothers quarreled and the army split up.[2] Oranyan's force was too small to make a successful attack, so he wandered the southern shore until reaching Bussa. There the local chief entertained him and provided a large snake with a magic charm attached to its throat.
The chief instructed Oranyan to follow the snake until it stopped somewhere for seven days and disappeared into the ground. Oranyan followed the advice and founded Oyo where the serpent stopped. The site is remembered as Ajaka. Oranyan made Oyo his new kingdom and became the first "oba" (meaning 'king' or 'ruler' in the Yoruba language) with the title of "Alaafin of Oyo" (Alaafin means 'owner of the palace' in Yoruba). He left all his treasures in Ife and allowed another king named Adimu to rule there.[3]
Oranyan, the first oba (king) of Oyo, was succeeded by Oba Ajaka, Alaafin of Oyo. Ajaka was deposed, because he lacked Yoruba military virtue and allowed his sub-chiefs too much independence. Leadership was then conferred upon Ajaka's brother, Shango, who was later deified as the deity of thunder and lightning. Ajaka was restored after Shango's death. Ajaka returned to the throne thoroughly more warlike and oppressive. His successor, Kori, managed to conquer the rest of what later historians would refer to as metropolitan Oyo.[3]
The heart of metropolitan Oyo was its capital at Oyo-Ile, (also known as Katunga or Old Oyo or Oyo-oro).[4] The two most important structures in Oyo-Ile was the 'afin,' or palace of the Oba, and his market. The palace was at the center of the city close to the Oba's market called 'Oja-oba'. Around the capital was a tall earthen wall for defense with 17 gates. The importance of the two large structures (the palace and the Oja Oba) signified the importance of the king in Oyo.
Oyo had grown into a formidable inland power by the end of the 14th century. For over a century, the Yoruba state had expanded at the expense of its neighbors. During the reign of Onigbogi, Oyo suffered military defeats at the hands of the Nupe led by Tsoede.[5] Sometime around 1535, the Nupe occupied Oyo and forced its ruling dynasty to take refuge in the kingdom of Borgu.[6] The Nupe sacked the capital, destroying Oyo as a regional power until the early 17th century.[7]
The Yoruba of Oyo went through an interrugnum of 80 years as an exiled dynasty after its defeat by the Nupe. They re-established Oyo as more centralized and expansive than ever. The people created a government that established its power over a vast empire.[6] During the 17th century, Oyo began a long stretch of growth, becoming a major empire.[7] Oyo never encompassed all Yoruba-speaking people, but it was the most populous kingdom in Yoruba history.[8]
Oyo Empire and surrounding states, c. 1625.
The key to Yoruba rebuilding of Oyo was a stronger military and a more centralized government. Taking a cue from their Nupe enemies (whom they called "Tapa"), the Yoruba rearmed with armor and cavalry.[6] Oba Ofinran, Alaafin of Oyo, succeeded in regaining Oyo's original territory from the Nupe.[5] A new capital, Oyo-Igboho, was constructed, and the original became known as Old Oyo.[5] The next oba, Egunoju, conquered nearly all of Yorubaland.[5] After this, Oba Orompoto led attacks to obliterate the Nupe to ensure Oyo was never threatened by them again.[5] During the reign of Oba, Ajiboyede, he held the first Bere festival, an event to celebrate peace in the kingdom. Celebrated regularly, it would retain much significance among the Yoruba long after the fall of Oyo.[5]
Under his successor, Abipa, the Yoruba repopulated Oyo-Ile and rebuilt the original capital.[5] Despite a failed attempt to conquer the Benin Empire sometime between 1578 and 1608,[5] Oyo continued to expand. The Yoruba allowed autonomy to the southeast of metropolitan Oyo, where the non-Yoruba areas could act as a buffer between Oyo and Imperial Benin.[9] By the end of the 16th century, the Ewe and Aja states of modern Benin were paying tribute to Oyo.[10]
The reinvigorated Oyo Empire began raiding southward as early as 1682.[11] By the end of its military expansion, Oyo's borders would reach to the coast some 200 miles southwest of its capital.[12] It met little serious opposition until the early 18th century. In 1728, the Oyo Empire invaded the Kingdom of Dahomey in a major campaign of its cavalry.[11][13] Dahomey warriors, on the other hand, had no cavalry but many firearms. Their gunshots scared the Oyo cavalry horses and prevented their charging.[14] Dahomey's army also built fortifications such as trenches, which forced the Oyo army to fight as infantry.[15] The battle lasted four days, but the Yoruba were eventually victorious after reinforcements arrived.[15] Dahomey was forced to pay tribute to Oyo. The Yoruba invaded Dahomey seven times before finally subjugating the small kingdom in 1748.[16]
With its cavalry, Oyo campaigned successfully in conquest and suppression over great distances. The Oyo army was able to attack defensive fortifications, but it was harder to supply an army, and they withdrew when supplies ran out.[17] The Oyo did not use guns in its major conquests. The military waited until the 19th century to adopt them.[17] In 1764, a joint Oyo-Dahomey force crushed an Asante army.[11] The Oyo victory defined borders between the two states.[11] Oyo led a successful campaign into Mahi territory north of Dahomey in the late 18th century.[11] The Yoruba also used the forces of their tributaries; for instance, they accomplished a 1784 naval blockade of Badagri with an Oyo-Dahomey-Lagos force.[18]
At the beginning, the people were concentrated in metropolitan Oyo. With imperial expansion, Oyo reorganized to better manage its vast holdings within and outside of Yorubaland. It was divided into four layers defined by relation to the core of the empire.[19] These layers were Metropolitan Oyo, southern Yorubaland, the Egbado Corridor and Ajaland.
Metropolitan Oyo corresponded, more or less, to the Oyo state prior to the Nupe invasion.[19] This was the hub of the empire, where the Yoruba spoke the Oyo dialect.[9] Metropolitan Oyo was divided into six provinces, with three on the west side of the Ogun River and three to the river's east.[9] Each province was supervised by a governor appointed directly by the Alaafin of Oyo.[20]
The second layer of the empire was composed of the towns closest to Oyo-Ile, which were recognized as brothers.[19] This area was south of metropolitan Oyo, and its Yoruba inhabitants spoke different dialects from that of Oyo.[9] These tributary states were led by their own rulers, titled Obas,[20] who were confirmed by the Alaafin of Oyo.[20]
The empire's third layer was the Egbado Corridor southwest of Yorubaland. This area was inhabited by the Egba and Egbado, and guaranteed Oyo's trade with the coast. The Egba and Egbado tributaries were allowed, like their Yoruba counterparts, to rule themselves. They were, however, supervised by Ajele.[19] These were agents appointed by the Alaafin of Oyo to oversee his interest and monitor commerce. The lead representative of Oyo in the corridor was the Olu, ruler of the town of Ilaro.[12]
Ajaland was the last layer added to the empire. It was the most restive and distant, and kept in line with threats of expeditions against it.[19] This territory extended from the non-Yoruba areas west of the Egbado Corridor far into Ewe controlled territory in modern Togo.[9] This area, like all tributary states, was allowed a fair degree of autonomy as along as taxes were paid, the orders from Oyo were strictly followed, and access to local markets was provided to Oyo merchants.[10] The Oyo often demanded tribute in slaves. The tributary sometimes made war on other peoples to capture slaves for this.[21] Oyo punished disobedience by wholesale slaughter of the community, as it accomplished in Allada in 1698.[10]
The Oyo Empire developed a highly sophisticated political structure to govern its territorial domains. Scholars have not determined how much of this structure existed prior to the Nupe invasion. Some of Oyo's institutions are clearly derivative of early accomplishments in Ife. After reemerging from exile in the early 17th century, Oyo took on a noticeably more militant character. The influence of an aggressive Yoruba culture is exemplified in the standards placed on the oba (king) and the roles of his council.
The oba (meaning 'king' in the Yoruba language) at Oyo, who was referred to as the Alaafin of Oyo, (Alaafin means 'owner of the palace' in Yoruba), was the head of the empire and supreme overlord of the people.[22] He was responsible for keeping tributaries safe from attack, settling internal quarrels between sub-rulers, and mediating between those sub-rulers and their people.[22] The Alaafin of Oyo was also expected to give his subordinates honors and presents.[22] In return, all sub-rulers had to pay homage to the Oba and renew their allegiance at annual ceremonies.[20] The most important of these was the Bere festival, marking the acclamation of successful rule by the Alaffin.[20] After the Bere festival, peace in Yorubaland was supposed to last for three years.[20]
The Oyo Empire was not a hereditary monarchy, nor an absolute one.[22] The Oyo Mesi selected the Alaafin. He was not always directly related to his predecessor, although he did have to be descended from Oranyan (also known as Oranmiyan), a son of Oduduwa (also known as Odudua, Odua ) and to hail from the Ona Isokun ward (which is one of the three royal wards).[22] At the beginning of the Oyo Empire, usually the Alaafin's oldest son succeeded his father to the throne. But, this sometimes led to the oldest son, i.e. the first-born prince, the Aremo, hastening the death of his father. Independently of the possible succession, the Aremo was quite powerful in his own right. For instance, by custom the Alaafin abstained from leaving the palace, except during the important festivals, which in practice curtailed his power. By contrast, the Aremo often left the palace. This led noted historian S. Johnson to observe: "The father is the king of the palace, and the son the King for the general public".[23] The two councils which checked the Alaafin had a tendency to select a weak Alaafin after the reign of a strong one to keep the office from becoming too powerful.[24]
The Alaafin of Oyo appointed certain religious and government officials, who were usually eunuchs.[25] These officials were known as the ilari or half-heads, because of the custom of shaving half of their heads and applying what was believed to be a magical substance into it.[26] The hundreds of Ilari were divided evenly among the sexes.[26] Junior members of the Ilari did menial tasks, while seniors acted as guards or sometimes messengers to the other world via sacrifice.[26] Their titles related to the king, such as oba l'olu ("the king is supreme") or madarikan ("do not oppose him").[26] They carried red and green fans as credentials of their status.[26]
All sub-courts of Oyo had Ilari who acted as both spies and taxmen.[20] Oyo appointed these to visit and sometimes reside in Dahomey and the Egbado Corridor to collect taxes and spy on Dahomey's military successes, so that the Alaafin of Oyo could get his cut.[27] Similar officials had existed in Ife, as attested by terracotta art depicting them.[27]
While the Alaafin of Oyo was supreme overlord of the people, he was not without checks on his power. The Oyo Mesi and the Yoruba Earth cult known as Ogboni kept the Oba's power in check.[25] The Oyo Mesi spoke for the politicians while The Ogboni spoke for the people backed by the power of religion.[24] The power of the Alaafin of Oyo in relation to the Oyo Mesi and Ogboni depended on his personal character and political shrewdness.
The Oyo Mesi were seven principal councilors of the state. They constituted the Electoral Council and possessed legislative powers, similar to today's United States Congress. The Bashorun, Agbaakin, Samu, Alapini, Laguna, Akiniku and a Ashipa are the seven members of this council. They represented the voice of the nation and had the chief responsibility of protecting the interests of the empire. The Alaafin was required to take counsel with them whenever any important matter affecting the state occurs. Each man had a state duty to perform at court every morning and afternoon. Each mesi had a deputy whom they would send to the Alaafin if his absence was unavoidable.
They controlled the military. The head of the council, the Bashuron, consulted the Ifa oracle for approval from the gods. New alaafins of Oyo were seen as appointed by the gods. They were regarded as Ekeji Orisa, meaning "companion of the gods." The Bashuron was a sort of prime minister. He had the final say on the nomination of the new Alaafin. The Oyo Mesi developed as a check on the Alaafin's power. The Bashorun's power rivaled that of the Alaafin. For example, the Bashorun orchestrated many religious festivals; in addition to being commander-in-chief of the army, this gave him considerable independent religious authority.
The Oyo Mesi does not enjoy an absolute power or influence, and while the Oyo Mesi may wield political influence, the Ogboni represented the popular opinion backed by the authority of religion, and therefore the view of the Oyo Mesi could be moderate by the Ogboni. And most interestingly, there are checks and balances on the power of the Alafin and the Oyo Mesi and thus no one is arrogated absolute power. The Ogboni was a very powerful secret society composed of freemen noted for their age, wisdom and importance in religious and political affairs.[25] Its members enjoyed immense power over the common people due to their religious station. A testament to how widespread the institution was is the fact that there were Ogboni councils at nearly all sub-courts within Yorubaland.[25] Aside from their duties in respect to the worship of the earth, they were responsible for judging any case dealing with the spilling of blood.[25] The leader of the Ogboni, the Oluwo, had the unqualified right of direct access to the Alaafin of Oyo on any matter.[25]
Chief among the responsibilities of the Bashorun was the all important festival of Orun. This religious divination, held every year, was to determine if the members of the Mesi still held favor with the Alafin. If the council decided on the disapproval of the Alafin, the Bashorun presented the Alafin with an empty calabash, or parrot's egg as a sign that he must commit suicide. This was the only way to remove the Alafin because he could not be legally deposed. Once given the parrot's egg, the Bashorun would proclaim, "the gods reject you, the people reject you, the earth rejects you." The Alafin, his eldest son, and the Samu, his personal counselor and a member of the Oyo Mesi all had to commit suicide in order to renew the government all together. The process and suicide ceremony took place during the Orun festival.
There was a high degree of professionalism in the army of the Oyo Empire.[28] Its military success was due in large part to its cavalry as well as the leadership and courage of Oyo officers and warriors.[28] Because its main geographic focus was north of the forest, Oyo enjoyed easier farming and thus a steady growth in population.[28] This contributed to Oyo's ability to consistently field a large force. There was also an entrenched military culture in Oyo where victory was obligatory and defeat carried the duty of committing suicide.[24] This do-or-die policy no doubt contributed to the military aggressiveness of Oyo's generals.[24]
The Oyo Empire was the only Yoruba state to adopt cavalry; it did so because most of its territory was in the northern savannah.[13] The origin of the cavalry is disputed; however, the Nupe, Borgu and Hausa in neighboring territories also used cavalry and may have had the same historical source.[29] Oyo was able to purchase horses from the north and maintain them in metropolitan Oyo because of partial freedom from the tsetse fly.[30] Cavalry was the long arm of the Oyo Empire. Late 16th and 17th century expeditions were composed entirely of cavalry.[13] There were drawbacks to this. Oyo could not maintain its cavalry army in the south but could raid at will.[11]
Cavalry in highly developed societies such as Oyo was divided into light and heavy.[13] Heavy cavalry on larger imported horses was armed with heavy thrusting lances or spears and also with swords.[13] Light cavalry on smaller indigenous ponies was armed with throwing spears or bows.[31] Oyo's cavalry forces included not only nobles, the norm in West African warfare, but foreign slaves from the Hausa, Nupe and Bornu states.[32]
Infantry in the region around the Oyo Empire was uniform in both armor and armament. All infantry in the region carried shields, swords and lances of one type or another.[11] Shields were four feet tall and two feet wide and made of elephant or ox hide.[33] A 3-foot-long (0.91 m) heavy sword was the main armament for close combat.[33] The Yoruba and their neighbors used triple barbed javelins which could be thrown accurately from about 30 paces.[11]
The Oyo Empire, like many empires before it, used both local and tributary forces to expand its domains. The structure of the Oyo military prior to its imperial period was simple and closer aligned to the central government in metropolitan Oyo. This may have been fine in the 15th century when Oyo controlled only its heartland. But to make and maintain farther conquest, the structure underwent several changes.
Oyo maintained a semi-standing army of specialist cavalry soldiers called the Eso or Esho.[34] These were 70 junior war chiefs who were nominated by the Oyo Mesi and confirmed by the Alaafin of Oyo.[34] The Eso were appointed for their military skill without regard to heritage and were led by the Are-Ona-Kakanfo.[24]
After Oyo's return from exile, the post of Are-Ona-Kakanfo was established as the supreme military commander.[35] He was required to live in a frontier province of great importance to keep an eye on the enemy and to keep him from usurping the government.[24] During Oyo's imperial period, the Are-Ona-Kakanfo personally commanded the army in the field on all campaigns.[24]
Since the Are-Ona-Kakanfo could not reside near the capital, arrangements had to be made for the latter's protection in case of emergency. Forces inside metropolitan Oyo were commanded by the Bashorun, leading member of the Oyo Mesi.[35] As stated earlier, Metropolitan Oyo was divided into six provinces divided evenly by a river. Provincial forces were thus grouped into two armies, under the Onikoyi and the Okere for the east and west side of the river respectively.[35] Lesser war chiefs were known as Balogun, a title carried on by the soldiers of Oyo's successor state, Ibadan.[36]
Tributary leaders and provincial governors were responsible for collecting tribute and contributing troops under local generalship to the imperial army in times of emergency.[9] Occasionally, tributary leaders would be ordered to attack neighbors even without the backing of the main imperial army.[9] These forces were often utilized in Oyo's more distant campaigns on the coast or against western states like Asanteman or the Mahi.
Oyo became the southern emporium of the Trans-Saharan trade. Exchanges were made in salt, leather, horses, kola nuts, ivory, cloth and slaves.[30] The Yoruba of metropolitan Oyo were also highly skilled in craft making and iron work.[30] Aside from taxes on trade products coming in and out of the empire, Oyo also became wealthy off the taxes imposed on its tributaries. Taxes on the kingdom of Dahomey alone brought in an amount estimated at 638 thousand dollars a year.[28]
Oyo's imperial success made Yoruba a lingua franca almost to the shores of the Volta.[30] Toward the end of the 18th century, the Oyo army was neglected as there was less need to conquer.[19] Instead, Oyo directed more effort towards trading and acted as middlemen for both the Trans-Saharan and Trans-Atlantic slave trade.[19] Europeans bringing salt arrived in Oyo during the reign of King Obalokun.[5] Thanks to its domination of the coast, Oyo merchants were able to trade with Europeans at Porto Novo and Whydah.[10] Here the Oyo Empire's captives and criminals were sold to Dutch and Portuguese buyers.[37]
Oyo Empire and surrounding states circa 1700.
By 1680, the Oyo Empire spanned over 150,000 square kilometers.[1] It reached the height of its power in the 18th century.[10] And despite its violent creation, it was held together by mutual self-interest.[22] The government was able to provide unity for a vast area through a combination of local autonomy and imperial authority.[28]
Unlike the great savannah empires, of which Oyo may not be called a successor since it was a successor of Ife, there was little if any Muslim influence in the empire.[19] It is known that at least some Muslim officials were kept in Metropolitan Oyo,[38] and men capable of writing and calculating in Arabic were reported by French traders in 1787.[38]
The end of the 18th century marked the beginning of the Oyo Empire's downfall. In around 1789, Oba Abiodun is believed to have been killed by his son and successor, Awole.[30] A series of constitutional upheavals, dynastic intrigues and local particularism weakened the empire.[30] In 1796, Oba Awole was ousted by the government in an Illorin-centered revolt initiated by Afonja, the Are Ona Kakanfo. The revolt led to the secession of Ilorin, a Yoruba state that would play a crucial role in the destruction of Oyo. At his rejection by the council, he is said to have cursed the empire as he prepared to commit suicide.[39] After firing arrows in all directions he proclaimed:
"My curse be on you and your disloyalty and your disobedience, so let your children disobey you. If you send them on an errand, let them never return to bring you word again. To all points I shot my arrows, you will be carried as slaves. My curse will carry to the sea and beyond the seas. Slaves will rule over you, and you their masters will become slaves. Broken calabash can be mended but not a broken dish; so let my words be irrevocable."
As Oyo tore itself apart via political intrigue, its vassals began taking advantage of the situation to press for independence. The Egba, under the leadership of Lishabi, massacred the Ilari stationed in their area and drove off an Oyo punitive force.[9]
When Dahomey's King Gezo ascended the throne in 1818, he offered only a tiny piece of cloth and 2 bags of cowries to the Oyo tax collector saying that anything else would be disproportionate to Dahomey's wealth.[40] When four more envoys were sent from Oyo, Gezo had them beheaded.[40] An Oyo army was deployed and decisively defeated, ending Oyo's hegemony over Dahomey.[40] After gaining its independence, Dahomey began raiding the corridor.[12]
After Awole's rejection, Afonja, now master of Illorin, invited an itinerant Fulani scholar of Islam called Alim al-Salih into his ranks. By doing this, he hoped to secure the support of Yoruba Muslims (mainly slaves taking care of the Empire's horses) and volunteers from the Hausa-Fulani north in keeping Ilorin independent. Torn by internal struggle, Oyo could not defend itself against the Fulani.[39] Oyo-Ile was razed by the Fulani Empire in 1835 and the Oyo Empire collapsed in 1836,[41] once Afonja had been killed by the Fulani. Up to this day, the Illorin traditional ruler is an emir, whereas in the rest of Yoruba towns the kings are called oba or baale (Baale or Baba Onile meaning "father of the land" or "lord of the land").
After the destruction of Oyo-Ile, the capital was moved further south, to Ago d'Oyo. Oba Atiba sought to preserve what remained of Oyo by placing on Ibadan the duty of protecting the capital from the Ilorin in the north and northeast.[42] He also attempted to get the Ijaye to protect Oyo from the west against the Dahomeans.[42] The center of Yoruba power moved further south to Ibadan, a Yoruba war camp settled by Oyo commanders in 1830.[13]
Atiba's gambit failed, and Oyo never regained its prominence in the region. It became a protectorate of Great Britain in 1888 before further fragmenting into warring factions. The Oyo state ceased to exist as any sort of power 1896.[39] He died in died in 1905. (Oba Atiba otherwise called Atiba Atobatele did not die in 1905. He died in 1859; It was his son Adeyemi I and the 3rd Alaafin to rule in the present Oyo who died in 1905. See http://en.wikipedia.org/wiki/List_of_rulers_of_the_Yoruba_state_of_Oyo)During the colonial period, the Yoruba's were one of the most urbanized (living in city-like areas) group in Africa. About 22 % of the population lived in large areas with population exceeding 100,000 and over 50 % lived in cities of made up of 25,000 or more people. The index of urbanization in 1950 was close to that of the United States, excluding Ilorin. The Yoruba continue to be the most urbanised African ethnic group today. Old Oyo linked cities such as Ibadan, Osogbo, and Ogbomoso, which were some of the major cities that flourished after the collapse.[43]
- ^ a b Thornton 1998, p. 104.
- ^ Stride & Ifeka 1971 p. 290
- ^ a b Stride & Ifeka 1971, p. 291
- ^ Goddard 1971, pp. 207-211.
- ^ a b c d e f g h i Stride & Ifeka p. 292
- ^ a b c Oliver & Atmore 2001, p. 89.
- ^ a b Thornton 1999, p. 77.
- ^ Alpern 1998, p. 37.
- ^ a b c d e f g h Stride & Ifeka 1971, p. 296.
- ^ a b c d e Stride & Ifeka 1971, p. 293.
- ^ a b c d e f g h Thornton 1999, p. 79.
- ^ a b c Smith 1989, p. 122.
- ^ a b c d e f Smith 1989, p. 48.
- ^ Thornton 1999, p. 82.
- ^ a b Thornton 1999, p. 86.
- ^ Alpern 1998, p. 165.
- ^ a b Thornton 1999, p. 97.
- ^ Thornton 1999, p. 88.
- ^ a b c d e f g h Oliver & Atmore 2001, p. 95.
- ^ a b c d e f g Stride & Ifeka 1971, p. 297.
- ^ Alpern 1998, p. 34.
- ^ a b c d e f Stride & Ifeka 1971, p. 298.
- ^ Church Missionary Society, G.31 A.2/1888-9, Letter of S. Johnson to the Rev. J.B. Wood, 8 November 1887, as cited by Law R., The Oyo Empire c.1600-c.1836, p. 71 (1977)
- ^ a b c d e f g Stride & Ifeka 1971, p. 300.
- ^ a b c d e f Stride & Ifeka 1971, p. 299.
- ^ a b c d e Smith 1989, p. 12.
- ^ a b Smith 1989, p. 10.
- ^ a b c d e Stride & Ifeka 1971, p. 301.
- ^ Law 1975, pp. 1-15.
- ^ a b c d e f Stride & Ifeka 1971, p. 302.
- ^ Smith 1989, p. 50.
- ^ Smith 1989, p. 43.
- ^ a b Thornton 1999, p. 80.
- ^ a b Smith 1989, p. 56.
- ^ a b c Smith 1989, p. 53.
- ^ Smith 1989, p. 57.
- ^ Smith 1989, p. 31.
- ^ a b Smith 1989, p. 20.
- ^ a b c Stride & Ifeka 1971, p. 303.
- ^ a b c Alpern 1998, p. 166.
- ^ Alpern 1998, p. 196.
- ^ a b Smith 1989, p. 123.
- ^ Bascom 1962, pp. 699-709.
- Alpern, Stanley B. (1998). Amazons of Black Sparta: The Women Warriors of Dahomey. New York University Press. ISBN 0-8147-0678-9.
- Bascom, William (Aug., 1962). "Some Aspects of Yoruba Urbanism". American Anthropologist 64 (4): 699–709. DOI:10.1525/aa.1962.64.4.02a00010. JSTOR 667787.
- Goddard, Stephen (Jun., 1971). "Ago That became Oyo: An Essay in Yoruba Historical Geography". The Geographical Journal (Blackwell Publishing) 137 (2): 207–211. DOI:10.2307/1796741. JSTOR 1796741.
- Law, Robin (1975). "A West African Cavalry State: The Kingdom of Oyo". The Journal of African History 16 (1): 1–15. DOI:10.1017/S0021853700014079. ISSN 0021-8537. JSTOR 181095.
- Oliver, Roland (1975). The Cambridge History of Africa. Cambridge: Cambridge University Press. ISBN 0-521-20981-1.
- Oliver, Roland & Anthony Atmore (2001). Medieval Africa 1250-1800. Cambridge: Cambridge University Press. ISBN 0-521-79372-6.
- Smith, Robert S. (1989). Warfare & Diplomacy in Pre-Colonial West Africa Second Edition. Madison: University of Wisconsin Press. ISBN 0-299-12334-0.
- Stride, G.T. & C. Ifeka (1971). Peoples and Empires of West Africa: West Africa in History 1000-1800. Edinburgh: Nelson. ISBN 0-17-511448-X.
- Thornton, John K. (1999). Warfare in Atlantic Africa 1500-1800. London and New York: Routledge. ISBN 1-85728-393-7.
- Thornton, John (1998). Africa and Africans in the Making of the Atlantic World, 1400-1800 (Second Edition). Cambridge: Cambridge University Press. p. 340 Pages. ISBN 0-521-62724-9.
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Kehnide Salami, Yunusa Ph.D. "The Democratic Structure fo Yorub Political-Cultural Heritage." Department of Philosophy Obafemi Awolowo University Ile-Ife. 29 Apr. 2009. http://www.jpahafrican.com/docs/vol1no6/DemocraticStructreOf YoruaPoliticalCultrualsociety_vol1.no6.pdf
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