1942: Gadhafi is born to a Bedouin father in the central Libyan desert. His father was once jailed for opposing Italy's occupation from 1911 to 1941.
1969: As a 27-year-old captain, Gadhafi becomes Libya's undisputed ruler by overthrowing the monarchy in a largely peaceful coup.
1970s: Gadhafi makes changes to establish a socialist system. He nationalizes businesses, expels 20,000 Italians and closes a U.S. air base.
1980s: Gadhafi supports groups the United States considers terrorists, including the IRA and radical Palestinian factions. In 1986, U.S. jets bomb Libya after it is found responsible for the bombing of a Berlin disco frequented by U.S. troops.
1988: Suspected Libyan agents bomb Pan Am Flight 103 over Lockerbie, Scotland. The bombing killed 270 people, including 189 Americans.
1989: Libya is blamed for the bombing of a French airline over Niger. The attack killed 170 people.
1999: Gadhafi hands over two Libyans charged in the Lockerbie bombing.
2001: A Scottish court convicts Abdel Baset al-Megrahi of the Lockerbie bombing and sentences him to life in prison. The other suspect is acquitted.
2003: Libya takes responsibility for the Lockerbie bombing and agrees to pay up to $10 million to the relatives of each victim. It also announces that it will dismantle all weapons of mass destruction.
2009: Days before Gadhafi celebrates 40 years in power, he angers the international community by welcoming al-Megrahi home as a hero. Al-Megrahi was convicted of the Lockerbie bombing, but released on compassionate grounds because he was purportedly dying of cancer.
Feb. 21, 2011: Gadhafi's regime begins to falter. Diplomats and the justice minister resign, while air force pilots defect. Protesters claim control of Benghazi after some army units side with them.
The Associated Press contributed to this report.