UNITA's Jonas Savimbi was a competent leader and respected military commander who was a devout anti-Communist.
He fought staunchly against the Marxist MPLA government's FNLA army and their thousands of Cuban and Russian support troops in Angola.
In fact, the U.S. Reagen administration funded and equipped UNITA, providing them with Sidewinder missiles to bring down Cuban MI-24 choppers and MIGs, thus restricting the FNLA's air superiority in many areas.
Enter democracy in South Africa and the U.S. Clinton Administration, who signed an oil deal with Angola's Marxist despot government headed by Jose Eduardo De Santos.
With the Cubans now out of Angola, Dos Santos' rule was in jeopardy as UNITA were better equipped and trained and stated they would not respect any mineral treaties signed by the MPLA government
The Angolan government then hires "Executive Outcomes" (EO) a private army of former South African and Namibian troops (who were once upon a time Savimbi's allies and foes) to help eradicate UNITA
South Africa's first democratically elected president, Nelson Mandela gave his blessings for Eeben Barlow's EO to help train and aid the Angolan government eradicate the majority tribe in Angola
EO trained and aided the MPLA government's FNLA army to crush UNITA, even with ex SADF servicemen flying MIGs and choppers sorties.
There are many rumours around Savimbi's demise, but those "in the know" (ex EO upper ranks) eventually stated publicly that Savimbi was executed while unarmed as there was a "no prisoner" clause in the EO contract with the Angolan government. They wanted him dead....
An FNLA soldier took the credit for killing Savimbi and was hailed a "national hero"
Thereafter UNITA fell apart, was disbanded and their former foot soldiers were disarmed by the UN and placed into Angolan government "re-education" camps where tens of thousands of these former UNITA foot soldiers were systematically starved to death before Angola's first "free and fair elections" All this while the world turned a blind eye and a deaf ear to UNITA's politicians who protested these actions...
So, call Savimbi a "warmonger" if you please, but his demise was also the demise of his tribe in the African tradition of clandestine African ethnic cleansing.
NB: I served in the SADF as an immigrant conscript and was in Angola. I've been in Jamba (which was UNITA's HQ) and he was a giant of a man, well educated, well spoken and respected by those who were fortunate enough to meet and speak with him in person. I didn't speak with him, but he was always waving, greeting and very accommodating to those who helped him in his quest to prevent Angola turning into another Soviet Union puppet state
The bottom line, there are no losers and winners in war, only those who die or survive...