The Mongol Empire (Mongolian: listen (help·info) Mongol-yn Ezent Güren; Cyrillic: Монголын эзэнт гүрэн; Kazakh: Моңғол қағандығы) existed during the 13th and 14th centuries A.D., and was the largest contiguous land empire in human history. Beginning in the Central Asian steppes, it eventually stretched from Eastern Europe to the Sea of Japan, covering large parts of Siberia in the north and extending southward into Southeast Asia, the Indian subcontinent, and the Middle East. It is commonly referred to as the largest contiguous empire in the history of the world. At its greatest extent it spanned 9,700 km (6,000 mi), covered an area of 24,000,000 km² (9,300,000 sq mi), 16% of the Earth's total land area, and held sway over a population of 100 million.

The Mongol Empire emerged from the Mongol tribes of modern-day Mongolia under the leadership of Genghis Khan, and subsequently the mixture with other Turkic tribes in the region. Genghis Khan was proclaimed ruler of all Mongols in 1206. The empire grew rapidly under his rule and then under the rule of his descendants, who sent invasions in every direction. The vast transcontinental empire which connected the east with the west with an enforced "Pax Mongolica" allowed trade, technologies, commodities and ideologies to be disseminated and exchanged across Eurasia.

Genghis Khan (/ˈɡɛŋɡɪs ˈkɑːn/ or /ˈdʒɛŋɡɪs ˈkɑːn/,Mongol: [tʃiŋɡɪs xaːŋ] ( listen); 1162? – August 1227), born Temujin, was the founder and Great Khan (emperor) of the Mongol Empire, which became the largest contiguous empire in history after his death.

He came to power by uniting many of the nomadic tribes of northeast Asia. After founding the Mongol Empire and being proclaimed "Genghis Khan", he started the Mongol invasions that resulted in the conquest of most of Eurasia. These included raids or invasions of the Kara-Khitan Khanate, Caucasus, Khwarezmid Empire, Western Xia and Jin dynasties. These campaigns were often accompanied by wholesale massacres of the civilian populations – especially in Khwarezmia. By the end of his life, the Mongol Empire occupied a substantial portion of Central Asia and China.

Before Genghis Khan died, he assigned Ögedei Khan as his successor and split his empire into khanates among his sons and grandsons. He died in 1227 after defeating the Western Xia. He was buried in an unmarked grave somewhere in Mongolia at an unknown location. His descendants went on to stretch the Mongol Empire across most of Eurasia by conquering or creating vassal states out of all of modern-day China, Korea, the Caucasus, Central Asian countries, and substantial portions of modern Eastern Europe, Russia and the Middle East. Many of these invasions resulted in the large-scale slaughter of local populations, which have given Genghis Khan and his empire a fearsome reputation in local histories.

Kublai Khan ( /ˈkuːblə ˈkɑːn/; Mongolian: Хубилай хаан, Xubilaĭ xaan; Middle Mongolian: Qubilai Qaγan, "King Qubilai"; September 23, 1215 – February 18, 1294), born Kublai (Mongolian: Хубилай, Xubilaĭ; Middle Mongolian: Qubilai; Chinese: 忽必烈; pinyin: Hūbìliè; also spelled Khubilai) and also known by the temple name Shizu (Chinese: 元世祖; pinyin: Yuán Shìzǔ; Wade–Giles: Yüan Shih-tsu), was the fifth Great Khan of the Mongol Empire from 1260 to 1294 and the founder of the Yuan Dynasty in China.

As he was the second son of Tolui and Sorghaghtani Beki, and a grandson of Genghis Khan, he claimed the title of Khagan of the Ikh Mongol Uls (Mongol Empire) in 1260 after the death of his older brother Möngke in the previous year, though his younger brother Ariq Böke was also given this title in the Mongolian capital, Karakorum. Kublai won the battle against Ariq Böke in 1264 and the succession war marked the beginning of disunity in the empire. Kublai's real power was limited to China and Mongolia (which was the Yuan Dynasty, or the Mongol Dynasty) after the victory over Ariq Böke, though his influence still remained in the Ilkhanate and, to a far lesser degree, in the Golden Horde in the western parts of the Mongol Empire. If one counts the Mongol Empire at that time as a whole, his realm reached from the Pacific to the Urals, from Siberia to modern day Afghanistan – one fifth of the world's inhabited land area.