[4] Kiir was born to the Dinka ethnic group and joined Anyanya rebels fighting for Southern independence during the First Sudanese Civil War in 1967.

[6] In 1983, when John Garang joined an army mutiny he had been sent to put down, Kiir and other Southern leaders defected to the rebel Sudan People's Liberation Army/Movement (SPLA/M) in the second civil war.

[6] Following the signing of the Comprehensive Peace Agreement formally ending the war in January 2005, Garang was sworn in as the Vice President of the Republic of Sudan.

Although the vote on both the national and sub-national level was criticized by democratic activists and international observers, the overwhelming margin of Kiir's re-election was noted by some media as being "Step One" in the process of secession.

[15] A few weeks later, he publicly addressed members of the military and police to warn them that rape, torture, and other human rights violations carried out by armed personnel would be considered criminal acts and prosecuted aggressively by the Ministry of Justice.

On 18 June 2013, Kiir issued an order lifting the immunity of two ministers in the national government pending investigations into an alleged corruption case in which they appeared to be implicated.

In July 2013, Kiir sacked his entire cabinet, including his vice president, Riek Machar, ostensibly to reduce the size of government.

According to investigations carried out by the UN, 800 people from both ethnic groups were killed between December 2011 and February 2012, while women and children were abducted and property was looted and destroyed.

[19] Throughout the Jonglei disarmament "Operation Restore Peace" which began in March 2012 and continued throughout the year, soldiers were ordered to and assumed the responsibility of extrajudicial killings, severe beatings, binding people with rope, and torture to extract "information" regarding the whereabouts of weapons.

After rumors about a planned coup surfaced in Juba in late 2012, Kiir began reorganizing the senior leadership of his government, party and military on an unprecedented scale.

[23] Moi Peter Julius, who was a political reporter for a South Sudanese newspaper The Corporate, was found murdered late on the night of 19 August 2015 in a residential area of Juba after being shot twice from behind.

Six staff of the South Sudan Broadcasting Corporation were subsequently arrested on 7 January 2023 in relation to video of the urination, which was widely distributed online.

He declared the East African Community to be "at the center of our hearts" due to its members' support of South Sudan during the Sudanese civil wars.

[29] On 20 December 2011, Kiir visited Israel to thank it for its support during the First Sudanese Civil War from 1956 to 1972,[30] and met with Israeli president Shimon Peres to discuss establishing an embassy in Jerusalem, which would make South Sudan the first country to have one in that city.

[31] After the outbreak of the South Sudanese civil war, Salva Kiir delivered a speech in January 2014 lashing out at the United Nations and "so-called humanitarian organizations", accusing them of supporting Riek Machar to try to overthrow him.

On 27 September, Kiir met Sudanese President Omar al-Bashir and signed eight agreements in Addis Ababa,[35] Ethiopia, which led the way to resume important oil exports and create a 10-kilometre (6 mi) demilitarized zone along their border.

South Sudan treated the attack as a gross violation of the cooperation agreement the two country's leaders signed in Addis Ababa, Ethiopia on 27 September.

Tensions rose between Kiir and his former vice president Riek Machar in December 2013 in the lead-up to a meeting of the National Liberation Council (NLC) of the ruling SPLM party.

[40] Kiir is reported to be the part-owner of ABMC Thai-South Sudan Construction Company Limited with Garang Deng Aguer and Benjamin Bol Mel.

[42] In the early months of 2017, parts of South Sudan experienced a famine following several years of instability in the country's food supply caused by civil war and drought.

More than 3 million people had been displaced by ongoing violence across the country, forcing families to abandon agricultural land and livestock, leaving them with few food resources to survive with.

[44] The worst fighting was in Unity State, where tens of thousands of people fled their homes due to a government offensive against opposition-held areas.

[48] In a politically charged social issue, it has been claimed that Kiir secretly married the daughter of former comrade, the late William Nyuon Bany, an ethnic Nuer and former leader of the SPLA.