Hezbollah, or Party of God, was conceived by Muslim clerics in the 1980s in response to the Israeli invasion of South Lebanon in 1982. The Shiite group has a political and military wing.

Hezbollah emerged in the 1980s as an amalgamation of Shiite militias and played a major role in the Lebanese civil war. It used guerrilla warfare to drive Israeli forces out of South Lebanon — Israel withdrew in 2000. Israel and Hezbollah fought another war in 2006. Its defense of Lebanon against Israel had won it cross-sectarian support and acceptance in Lebanese society.

Since its creation, Hezbollah has received military, financial and political support from Iran and Syria. Today, Hezbollah's military wing is more powerful than Lebanon's own army and has become a major regional paramilitary force.

Hezbollah turned its focus to politics following the end of Lebanon's 1975-1990 civil war. It represents a large section of the Lebanese Shiite population and is allied with other sectarian groups, including Christians. Their political development has mostly come under Hassan Nasrallah (pictured), who became the group's leader in 1992.

Unlike other parties in Lebanon's multi-sided 1975-1990 civil war, Hezbollah did not disband its armed wing. Some Lebanese political groups, such as Prime Minister Saad Hariri's Future Movement, want Hezbollah to put down its arms. Hezbollah argues its militant wing is necessary to defend against Israel and other external threats.

A number of countries and bodies, including the United States, Israel, Canada and the Arab League, consider Hezbollah a terrorist organization. However, Australia and most of the European Union differentiate between its legitimate political activities and its militant wing.

Hezbollah has been one of the main backers of Syrian President Bashar Assad in the country's civil war. Its entrance into the war helped save Assad, one of its chief patrons; secured weapons supply routes from Syria and formed a buffer zone around Lebanon against Sunni militant groups it feared would take over Syria. As a result it has won considerable support from Shiite communities in Lebanon.

Lebanon has long been at the center of regional power struggles, particularly between Saudi Arabia and Iran. However, Hezbollah's military and political ascendancy, as well as its intervention in Syria, have also helped stoke Sunni-Shiite sectarian tensions in Lebanon and across the region.

Iran and Hezbollah have increased their political and military strength through the war in Syria. Israel views this as a threat and has carried out dozens of airstrikes on Iran/Hezbollah targets in Syria. Israel has vowed to not let Iran and Hezbollah create a permanent presence in Syria. There is growing concern of another war between Hezbollah and Israel that could draw in Iran.