Sakher Habash, the Palestinian revolutionary and intellectual who died on Sunday after a stroke aged 70, devoted the greater part of his life to the Palestinian struggle.

Known by his nom de guerre Abu Nizar, Habash was a founding member of the Fatah Party and although he supported the Oslo process of talks with Israel in the mid-1990s, he never rejected armed resistance. Violence, he argued, was a legitimate way for Palestinians to struggle for their rights.

To the end, like his lifelong compadre Yasser Arafat, Habash donned the revolutionary uniform.

In 2002, after the second intifada had broken out and Israeli forces invaded Ramallah, he even picked up arms one last time, and holed up in a building to repel the invading Israeli tanks.

He also cultivated other interests, was a prolific writer of both poetry and history, writing among other things a history of the Fatah movement, and became known as one of the party’s intellectuals.

“He was a multifaceted man,” said Hanan Ashrawi, a member of the executive committee of the Palestinian Liberation Organisation. “He was an avid reader and writer. Every meeting we had, he would sit down and write a poem and send it to me afterwards.”

Habash regularly hosted members of every faction as well as community leaders at his home in Ramallah, and Palestinian unity was very much a priority for him.

“He was a unifier. He was very pleasant and very positive,” Ms Ashrawi said. “Even after he had his first stroke, his innate humanity always shone through. He was always looking for productive ways to solve problems.”

Perhaps as a result of his close reading of history, Habash had a sense of propriety. He made it his business to make sure that Palestinians who had been killed in fighting with Israel were remembered and pressured local authorities to name streets after them.

He also maintained an unshakeable faith in the Palestinian cause and never wavered in calling on others to do the same.

Foreseeing the potential dangers of the Israeli withdrawal from the Gaza Strip in his last interview with this reporter, in 2004, he warned that the “upcoming phase requires even more steadfastness, patience, unity and preparedness for sacrifice”. This, he added, had to be accompanied by “absolute faith in inevitable victory”.

Habash was born in 1939 in a village near Jaffa in what is now Israel. In 1948, his family fled the fighting and ended up in refugee camps in the West Bank, first in Ramallah then in Nablus.

In the late 1950s, Habash helped found Fatah, which evolved mainly out of young disaffected Palestinian refugees in Egypt and Gaza, under the leadership of Arafat. But it was in the West Bank that the nationalist movement first made an effect, with its philosophy of low-level guerrilla warfare against Israel conducted outside the control of Arab states.

Fatah’s first major guerrilla attack was in 1965, when fighters tried and failed to sabotage an Israel National Water Carrier station, which had recently begun diverting vast amounts of water from the Jordan River. Two years later, Fatah joined the PLO, but the movement only cemented its reputation after the 1967 war, notably at the battle of Karameh, Jordan, in 1968 where Fatah fighters successfully held off the Israeli army with support from the Jordanian army.

That battle convinced most Palestinians of the logic of Fatah’s philosophy, and Yasser Arafat was elected chairman of the PLO the next year, a position he held until his death.

However, Fatah’s guerrilla activity also saw it run afoul of Jordan, where the bulk of the movement resided, both as a result of punitive Israeli strikes on Jordanian targets and the behaviour of the movement’s fighters, who had almost created a state within a state. This culminated in September 1970, when the Jordanian army ousted Fatah from the country, forcing the movement to move its headquarters to Lebanon.

There, Habash became Arafat’s military adviser and was also responsible for recruitment. The influx of Palestinian fighters in Lebanon, however, destabilised that country, and the killing of 26 Fatah trainees in 1975 by Phalangist forces sparked Lebanon’s 15-year-long civil war, which eventually saw the Israeli army invade and force Fatah out once again.

Throughout this period, Habash remained close to Arafat, and he followed him to Tunis. Many years later, in 2004, Habash would describe the fighting in Lebanon as the darkest time in the Palestinian struggle. Compared to that, he said, the current division between Fatah and Hamas was minor.

By then, a member of Fatah’s ruling central committee, Habash had endorsed the movement’s shift to political negotiations with Israel under the Oslo process.

His wife, three sons and a daughter survive him.