Algeria FRANCAIS of the Dinka ethnic group, Garang was born into a poor family in Wagkulei village, near Bor in the upper Nile region of Sudan. An orphan by the age of ten, he had his fees for school paid by a relative, going to schools in Wau and then Rumbek. In 1962 he joined the first Sudanese civil war, but because he was so young, the leaders encouraged him and others his age to seek an education. Because of the ongoing fighting, Garang was forced to attend his secondary education in Tanzania. After winning a scholarship, he went on to earn a B.A. in economics in 1969 from Grinnell College. He was known there for his bookishness. He was offered another scholarship to pursue graduate studies at the University of California at Berkeley, but chose to return to Tanzania and study East African agricultural economics as a Thomas J. Watson Fellow at the University of Dar es Salaam. As a member of the University Students' African Revolutionary Front, a student group at the university, he made the acquaintance of Yoweri Museveni, who would go on to become president of Uganda and a close ally. However, Garang soon decided to return to Sudan and join the rebels.

The civil war ended with the Addis Ababa agreement of 1972 and Garang, like many rebels, was absorbed into the Sudanese military. For eleven years, he was a career soldier and rose from the rank of captain to colonel after taking the Infantry Officers' Advanced Course at Fort Benning, Georgia. During this period he took four years academic leave and received a master's degree in agricultural economics and a Ph.D. in economics at Iowa State University, after writing a thesis on the agricultural development of Southern Sudan. By 1983, Col. Garang was the head of the Staff College in Omdurman. Dr. John Garang de Mabior (June 23, 1945 – July 30, 2005) was the vice president of Sudan and former leader of the rebel Sudan People's Liberation Army.

A member of the Dinka ethnic group, Garang was born into a poor family in Wagkulei village, near Bor in the upper Nile region of Sudan. An orphan by the age of ten, he had his fees for school paid by a relative, going to schools in Wau and then Rumbek. In 1962 he joined the first Sudanese civil war, but because he was so young, the leaders encouraged him and others his age to seek an education. Because of the ongoing fighting, Garang was forced to attend his secondary education in Tanzania. After winning a scholarship, he went on to earn a B.A. in economics in 1969 from Grinnell College. He was known there for his bookishness. He was offered another scholarship to pursue graduate studies at the University of California at Berkeley, but chose to return to Tanzania and study East African agricultural economics as a Thomas J. Watson Fellow at the University of Dar es Salaam. As a member of the University Students' African Revolutionary Front, a student group at the university, he made the acquaintance of Yoweri Museveni, who would go on to become president of Uganda and a close ally. However, Garang soon decided to return to Sudan and join the rebels.

The civil war ended with the Addis Ababa agreement of 1972 and Garang, like many rebels, was absorbed into the Sudanese military. For eleven years, he was a career soldier and rose from the rank of captain to colonel after taking the Infantry Officers' Advanced Course at Fort Benning, Georgia. During this period he took four years academic leave and received a master's degree in agricultural economics and a Ph.D. in economics at Iowa State University, after writing a thesis on the agricultural development of Southern Sudan. By 1983, Col. Garang was the head of the Staff College in Omdurman.