Ayatollah Ruhollah Khomeini, the architect and the face of the Iranian revolution, is seen by many as the embodiment of the principles of the Islamic Republic.
Rarely in history has a man who did not seek power come to wield so much of it.
He wanted to serve the people of Iran and throughout his life fought the regime's oppression, corruption and the Shah's opulent lifestyle. Forced exile empowered Khomeini even further, providing him with the freedom to speak out against Iran's ruling elite.
"He became the main speaker of the opposition inside Iran.... he was continuously attacking the Shah's brutality and because of that he gained the popular support of the people," says Ebrahim Yazdi, who was Iran's deputy prime minister in 1979.
The charismatic religious scholar managed to overthrow one of the strongest and most oppressive regimes in the world - and set Iran on a collision course with the West.
But who was Ayatollah Khomeini and what is his legacy?
Al Jazeera spoke to those who knew the man behind a revolution that shook the world.