During the five-year Luwero bush war, Dr Makumbi, who was now a senior official at Mulago Hospital, is believed to have been a top-level operative of the NRA, enabling the revolutionary rebels to access services and supplies from Mulago.
PIC: Makumbi and President Yoweri Museveni in Kayunga in 2000
The passing of Dr James Makumbi brings to an end a life of a courageous man spent nearly half a century in medical service, but did high level political work at a great risk to his life.
When the military coup took place in January 1971, Makumbi was a young physician at Mulago National Referral Hospital in Kampala.
Conflict between Idi Amin's government and that of Julius Nyerere started immediately because of the latter giving refuge to deposed ex-president Milton Obote.
Mulago Hospital did not escape getting dragged into the military-political disputes.
Soon after the coup, a senior Tanzanian police officer of mixed race, Hans Poppe, was killed by Ugandan troops after an incursion into Tanzania. Because the dead victim was of mixed race, with a light skin complexion, Amin saw an opportunity to claim that Tanzania was being backed by foreign socialist powers.
The dead policeman's body was taken to Mulago for temporary preservation and then paraded at the City Square like that of a Chinese colonel who had participated in an attack on Uganda.
A young Makumbi had been on duty to handle the body.
After the display, Amin's troops dumped the body at night on the Mulago grounds. Because Makumbi knew the truth of Poppe's identity, he sought permission of his senior, Dr Patrick Tumwine, and then gave the body permanent preservation treatment, and concealed it at the farthest storage place.
1994: Health minister Makumbi talks to Francis Mutazindwa after touring the areas where bodies of victims of Rwanda geneocide were floating in Rakai and Masaka
Makumbi spent the rest of the military regime's years hoping that the hidden body would never be discovered.
When the military regime fell, the Tanzanians, who had intelligence about what had happened, immediately came for the body and it was officially handed to their then foreign minister, Benjamin Mkapa - who, sixteen years later, became president.
Makumbi and Tumwine were hosted at the burial of Poppe in Iringa, Tanzania.
During the five-year Luwero bush war, Dr Makumbi, who was now a senior official at the hospital, is believed to have been a top level operative of the NRA, enabling the revolutionary rebels to access services and supplies from Mulago.
Some daring actions of the NRA operatives in Mulago included the treatment of seriously injured rebels, like Mugisha Muntu, who had been shot in the stomach and the preservation of the NRA's first commander, Ahmed Seguya.
When the NRM took power, Makumbi held several key positions in the army and health services, including as minister for health. In 2002, he became the UPDF's director of medical services.
During the eighth parliament, Makumbi was a member of parliament representing the army.
He held the honorary rank of brigadier.
The lowest point of Makumbi's public life was in 1995 while serving as health minister. He was abducted by the deadly Federal Democratic Alliance rebel Maj. Herbert Seddyabane Kimomeko Itongwa and held for three days.