(1975–91) Civil conflict resulting from tensions among Lebanon 's Christian and Muslim populations and exacerbated by the presence in Lebanon in the 1970s of fighters from the
In 1975 Lebanon's Muslims and leftists supported the PLO and sought more political power; its Christians, seeking to maintain their political dominance, opposed the PLO. The factions fought fiercely through early 1976, and Lebanon became effectively partitioned, with the Christians in power in the north and the Muslims in the south. Fearing an expanded war, both Israel and Syria intervened on the side of the Christians, who had begun to lose ground. Fighting continued at a lower level of intensity until 1982, when Israel invaded southern Lebanon to destroy Palestinian guerrilla bases; PLO forces were driven out of Beirut, and by 1985 Israel had withdrawn from most of Lebanon, which by then was split internally over whether to accept Syria's leadership. In 1989 the Christian leader General Michel Aoun attempted to drive Syria from Lebanon but was defeated, and the {{link=Arab League">Arab League mediated a peace deal; his removal from power in 1990 eliminated the largest obstacle to implementing a 1989 peace accord. In southern Lebanon, fighting between Israeli and Hezbollah forces continued even after Israel's final withdrawal from Lebanese territory in 2000.