He was born in Kireku Village, Ssingo County, in present-day Mityana District of the Central Region in 1926, the first-born to his parents.

The family eventually settled in Busega, a suburb of Kampala, the capital and largest city of Uganda.

In 1994, he was appointed vice-chancellor of Nkumba University, a private institution, serving in that capacity until his retirement in 2008.

Member of the 1963 Uganda Education Policy Review Commission chaired by Prof Edgar B.

Chairman, Salaries Review Commission for the East African Community General Fund Services 1971 - 1972 & 1974 - 1976 b.

Chairman of East African Airways Corporation Central Negotiating Council 1972 - 1976 11.

Delegate of Constituent Assembly - Representing Kyaddondo North (1994 - 1995) which drafted a new constitution for Uganda in which Kajubi unsuccessfully advocated the implementation of multi-party system, good governance and transparency in a federal arrangement that would accommodate Uganda's diverse regional interests.

Buganda Government Medal "Ekitiibwa Ky'Amafumu n'Engabo" (2011) Together with his wife, the Kajubi's were the parents of nine children with three sets of twins.

The majority of the now adult children live in the United States, where they migrated to pursue higher education in the late 1970s.

He was one of the first among Uganda's African elite to join the party in 1958, working closely with its leader Benedicto Kiwanuka to expand its reach.

He was carried to Mulago National Referral Hospital, where he was pronounced dead on arrival.

Following a period of national mourning, which included a period of lying in state at the Parliament Building and in his residence at Bugoloobi, a Kampala suburb, his remains were buried at Maya Village, approximately 25 kilometres (16 mi), by road, southwest of Kampala,[11] on 5 May 2012.