Igga was born in 1949.[6] He is variously described to stem from the Bari[7] and Zande[8] ethnic groups and he is a Roman Catholic. He studied economics in Cairo.[7]
Igga joined the South Sudanese rebels in 1985, training in Cuba and Ethiopia. He rose rapidly through the Sudan People's Liberation Army (SPLA) ranks,[7] and, by 1987, had the rank of major and commanded the Shakus Battalion.[9] The same year, he was Zonal Commander of Central Equatoria and a member of the SPLA/M High Command.[10] He was reportedly well-respected among civilians.[11]
Igga was one of the SPLA's most senior representatives during negotiations with SPLA-Nasir. He represented Garang as the head of the SPLA-Torit delegation at peace talks in Nairobi in November 1991. In 1993, he accompanied Garang to Nairobi for a peacemaking seminar in June and to Kampala for an IGAD-mediated dialogue with the Nasir faction.[12] Igga had known Lam Akol, one of the Nasir leaders, since their time together in the Cuban training camp.[8]
As chairman of the SPLM Political Affairs Commission, Igga established the Technical Committee of Intellectuals in February 2000. This committee was tasked with planning the civil administration of Southern Sudan.[13]
Igga read out the proclamation of independence when the two Sudan's divided.[7] He continued as the legislative speaker of the lower house from 2011 to 2013.[15]
President Salva Kiir appointed Igga as vice president on 23 August 2013 to replace Riek Machar, who he had dismissed a month previously. He was required to resign as speaker.[16] Igga was unanimously confirmed by the National Assembly on 26 August.[17]
On 19 August 2020, six of Igga's bodyguards were killed in a road ambush by National Salvation Front rebels in Igga's hometown of Lobonok. He was not with those bodyguards at the time.[19]
