In 1979 the world of Sunni Islam was in a state of drift and confusion. The Shia were enjoying a political triumph in Iran with the rise of Ayatollah Khomeini; Egypt had become the first Arab country to recognise Israel; and Islamist militants had seized Mecca's Grand Mosque, holding worshippers hostage for nearly two weeks during the annual Hajj pilgrimage.

When the Soviet Union committed troops to Afghanistan later that year, the conflict offered Sunni Islamists salvation and a cause that was their own - often with the blessing of Arab governments. The man who did more than anyone to lead and inspire this Sunni resurgence was Azzam. It was he who led the initial trickle of Arabs who went to support the Afghans, and eventually paved the way for thousands more to join them. In the process he became both military and spiritual leader to a growing band of Arab jihadis.

Little has been written about Azzam, although an examination of his life as a leader during the '80s reveals that challenges to al-Qaeda from within have dogged it from the start, and that the organisation is well placed to withstand the kind of dissent which now threatens it.

Azzam was born in 1941 in what was then British Mandatory Palestine. He earned a degree in Shariah law from Damascus University and a doctorate in Islamic jurisprudence from al-Azhar University in Cairo, the oldest institution of religious learning in the Islamic world. There he read books by Syed Qutb, the intellectual Godfather of modern Islamic fundamentalism, and met members of the Muslim Brotherhood, a movement he would later join. He also came into contact with both Ayman al-Zawahiri - the now de facto leader of al-Qaeda - and Omar Abdel-Rahman, the blind sheikh convicted of masterminding the 1993 bombing of the World Trade Centre.