Salva Kiir Mayardit (born September 13, 1951) is the first President of the Republic of South Sudan.

In the late 1960s, Kiir joined the Anyanya in the First Sudanese Civil War. By the time of the 1972 Addis Ababa Agreement, he was a low-ranking officer. In 1983, when John Garang joined an army mutiny he had been sent to put down, Kiir and other Southern leaders joined the rebel Sudan People's Liberation Movement (SPLM) in the second civil war. Garang had little military field experience and relied upon the more experienced Anyanya veterans, including Kiir, to actually carry out the ground war. Kiir eventually rose to head the SPLA, the SPLM's military wing. An attempt to remove Kiir from his post as SPLA chief of staff in 2004 nearly caused the organization to split.

Following the signing of the Comprehensive Peace Agreement formally ending the war in January 2005, which he had helped start, he was appointed Vice President of Southern Sudan. Perhaps significantly, former Southern Sudan president John Garang like Kiir is of the Dinka people, though of a different clan. After the death of Garang in a helicopter crash on 30 July 2005, Kiir was chosen to succeed to the post of First Vice President of Sudan and President of Southern Sudan. Kiir is popular among the military wing of the SPLM for his battlefield victories and among the populace for his unambiguous pro-secession stance.

Riek Machar Teny Dhurgon (born 1953), is the first vice-president of the independent Republic of South Sudan.

Riek Machar obtained a PhD in mechanical engineering in 1984 and then joined the rebel Sudan People's Liberation Movement/Army (SPLM/A) during the Second Sudanese Civil War (1983–2005). Riek fell out with the SPLM/A leader John Garang in 1991 and formed a splinter group, the SPLM/A-Nasir. In 1997 Riek made a treaty with the Government of Sudan and become head of the government-backed South Sudan Defense Force (SSDF). In 2000 he left the SSDF and formed a new militia, the Sudan People's Democratic Forces (SPDF), and in 2002 rejoined the SPLA as a senior commander. After the death of John Garang in July 2005, Riek Machar became vice-president of the autonomous Southern Sudan. He became vice-president of South Sudan on 9 July 2011 when the country became independent.

Riek Machar Teny Dhurgon was born in Leer, Unity State in 1953, the 26th son of the chief of both Ayod and Leer. He was brought up as a member of the Presbyterian church. Riek belongs to the Dok section of the Nuer people. He trained as an Engineer at Khartoum University, and obtained a PhD in Philosophy and strategic planning from the University of Bradford in 1984.