An Afghan insurgent leader whom America sponsored for years as “goodness personified” and who then fought for decades as one of its most feared enemies has died.

Jalaluddin Haqqani’s death is unlikely to have much military impact, as he ceded control of his eponymous Haqqani network to his son years ago, but it marks a symbolic generational shift. Haqqani was a key military leader for four decades of Afghanistan’s civil war, switching allies and backers but never putting down his weapons.

He first took up arms against Moscow with US support, then befriended Osama bin Laden and embraced the Taliban and finally came full circle to lead some of the most brutal attacks against American troops and the Afghan government they backed. He was accused of introducing suicide bombing to Afghanistan, a tactic responsible for thousands of deaths.

Haqqani was born in the south-eastern part of Afghanistan, the traditional home of his Zadran tribe that would later become his stronghold. His father owned land and ran businesses on both sides of the border with Pakistan, connections that would help make Haqqani a key player in the wars to come.

His military career began in earnest when Soviet forces overthrew the Afghan government in 1979 and Haqqani became a leader of resistance fighters based in Pakistan. He was a key figure in the cold war showdown that played out through the 1980s in Afghanistan, funded and feted by Washington and described by Charlie Wilson, a congressman at the time, as “goodness personified”.

He built up an enduring relationship with Pakistan’s powerful and secretive military Inter-Services Intelligence (ISI) agency. Decades later, after a 2011 attack on the US embassy in Kabul, Admiral Mike Mullen, the chairman of the Joint Chiefs of Staff, described the Haqqani network as “a veritable arm” of the ISI.

The trajectory from US ally to attacker began when the Soviet Union withdrew from Afghanistan, Washington’s interest in the region waned and the Afghan civil war spiralled into even greater violence and brutality.

During the long years of fighting, Haqqani had built up ties with Arab fighters, including close links with a wealthy Saudi militant named Osama bin Laden. In 1996 he pledged allegiance to the Taliban when the group captured Kabul, and during their brief years in government he was made a minister.

Those relationships led him into conflict with Washington. The first shots between former allies were cruise missiles, fired at his base by Americans in 1998. The US was trying to kill Bin Laden in retaliation for attacks on embassies in east Africa.

After the Taliban were toppled from power in the wake of the 9/11 attacks on the United States, Haqqani joined the insurgency against US-led foreign forces and the Afghan government.

His fighters operated more in coordination with other militants than under their command, and they became more feared than the mainstream Taliban. The Haqqani network became known for complex, bloody urban attacks on targets including banks, hotels and embassies, which often claimed a high civilian toll.

Most recently Afghan intelligence services have said the group was behind a truck bomb near the German embassy that killed 150 people, and a bomb hidden inside an ambulance that killed more than 100 in an attack widely denounced as a war crime.

In 2012 it was blacklisted by the US as a terrorist group, even though the Taliban remained off the list.

In recent years Haqqani had been seriously ill, battling Parkinson’s disease, according to the Associated Press. His son Sirajuddin has been in control long enough to have incurred a $5m bounty on his head, and in 2016 he was named deputy leader of the Taliban, cementing ties between the two groups.

Many Afghans thought the senior Haqqani had died some time ago, and that his death was being announced now for political reasons. “Jalaluddin was dead already. His re-death won’t help much,” Waheed Omer, the Afghan ambassador to Italy and a former presidential spokesman, said on Twitter.