Prehaps this will help:
1860: Druze-Christian war kills 12,000 Christians. French troops land to protect Maronite community.
1914-1918: Ottomans rule collapses, leaving mass starvation in Lebanon.
1920: League of Nations gives France mandate for Syria and Lebanon.
1926: Republican Constitution.
1932: France suspends Constitution.
1936: Phalange Party founded by Pierre Gemayel.
1939: France falls to Germany, which establishes Vichy France regime, continuing to administer Lebanon and Syria.
1941: British and Free French toops invade Lebanon. France promises full independence.
1943: Lebanon independent.
1946: France withdraws.
1948: Israel declare independence. Large numbers of Palestinan refugees arrive.
1953: Camille Chamoun elected President.
1956: Israel, backed by France and Britain, attacks Egypt in war over Suez Canal.
1957: Early elections, CIA support.
1958: Civil War between Muslims and Christians. President Camille Chamoun requests US Marines, which land in Beirut.
1964: PLO founded.
1967: June 5-10: Israel's Six Day War, leaving Israel occupying the West Bank, Gaza Strip, Sinai Peninsula (Egypt), and Golan (Syrian) Heights.
1968: Dec. 28: Israeli commandos raid Lebanon airport, destroying 13 aircraft. This was retaliation for Arab guerrillas machine-gunning an Israeli airliner in Athens on Dec. 26.
1969: Clashes between Lebanese army and PLO.
1970: PLO driven out of Jordan, set up headquarters in Beirut. Increase in PLO raids into Israel from southern Lebanon.
1973: Lebanon sieges PLO camps. Phalange Party
Apr. 10: Israeli commandos kill three Palestinian leaders in Beirut.
1974: Israel bombs Sabra and Shatila Palestinian refugee camps.
1975: Civil war starts after Phalangists attack PLO guerillas in Beirut.
1976: Civil war fighting intensifies. Christians massacre Palestinian inhabitants of Karantina and Tel el-Za'atar, Palestinians massacre Christians in Damour. Syria invited by Lebanese President Franjieh to intervene in Lebanese fighting. Syrian troops enter Lebanon and occupy all but far south of the country.
Aug. 12: Christians massacre Palestinians in Tel-al-Za'tar refugee camp.
1978: Israeli army invades southern Lebanon after Israeli civilians killed in PLO guerrilla raid. United Nations force (UNIFIL) sent to southern Lebanon. Israel forms proxy Lebanese militia in occupation zone. Syrian army shells Christians in east Beirut.
Mar. 12: Israeli army invades southern Lebanon, in retaliation for Israeli civilians killed in a PLO guerrilla raid.
Mar. 19: UN Security Council Resolution 425 calls for immediate Israeli withdrawal from Lebanon, and dispatches a new United Nations force (UNIFIL) to southern Lebanon.
1980-81: Increase in hostilities between Israel, Israeli-backed militias and PLO in southern Lebanon.
July 17: Israeli jets bomb PLO targets in Beirut, killing 300 people.
1982: Syrian troops besiege Syrian city of Hama after Muslim extremist uprising, killing up to 10,000 Sunni Muslims.
June 3: Palestinian terrorist group led by Abu Nidal attempts to assassinate Israel's Ambassador to Great Britain (Shlomo Argov).
June 6: Israel invades Lebanon.
Aug. 21: US mediation convinces PLO to leave Lebanon; multinational peacekeeping force arrives.
Aug. 23: Bashir Gemayel elected President.
Sept. 14: Bashir Gemayel assassinated.
Sept. 16-18: Phalangist militia enters Sabra and Shatila refugee camps, and massacres 700-800 Palestinians (Israeli estimate; other estimates range to 2000).
Sept. 21: Amin Gemayel (Bashir's brother) elected President.
1983: US Beirut Embassy destroyed by "Islamic Jihad" suicide bomber. Lebanese and Israeli governments agree on withdrawal of Israel troops from Lebanon on condition Syrian army also leaves. Syrians refuse to withdraw. Outbreak of fighting between Muslim forces and Lebanese government troops of President Amin Gemayel. Israeli army stages unilateral withdrawal from Chouf mountains east of Beirut to new front lines north of Sidon. French and US military headquarters razed by "Islamic Jihad" suicide bombers, killing more than 300 servicemen after US warships shell Muslim areas of Lebanon in support of Gemayel's government. Lebanese hold first "reconciliation" conference in Switzerland. Suicide bomber destroys Israeli military headquarters in Tyre.
May 17: Agreement signed between Lebanon and Israel, contingent on Syrian withdrawal; Syria and its allies attack Lebanese government forces.
Oct. 23: Suicide bombers kill 241 US Marines and 56 French troops in near-simultaneous truck bomb attacks.
1984: Multinational forces leave Lebanon after collapse of Lebanese government army. President Assad of Syria welcomes Gemayel to Damascus. Second Lebanese "reconciliation" conference in Switzerland fails. Abductions of Westerners in Beirut, including CIA station chief William Buckley, who dies after torture. Fierce Lebanese resistance -- mainly by Shia Muslims -- against Israeli occupation army in southern Lebanon.
Feb. 26: Last US Marines leave Lebanon.
1985: Israeli army withdraws from Sidon. Israel starts "iron fist" policy of military repression against guerrilla villages in southern Lebanon. Car bomb kills more than 80 civilians in Shia area of Beirut (CIA involvement later reported in Washington). Further abductions of Westerners in Lebanon, including journalist Terry Anderson of Associated Press. Israelis withdraw from Tyre. Shia Amal militia attacks Palestinian Beirut camps. Suicide bombers again attack Israelis and their allies in southern Lebanon.
1986: Shia Amal militia resumes attack on camps. More Westerners abducted. Hundreds of Palestinians die in camp sieges.
1987: Archbishop of Canterbury's envoy Terry Waite disappears in west Beirut while seeking release of US hostages. Shia and Druze militia war in Beirut prompts return of thousands of Syrian troops to Lebanese capital. Palestinian camps siege resumes.
1988: Failure of Lebanese parliament to elect new president. Rival prime ministers take office in west and east Beirut.
1989: General Michel Aoun, Christian Lebanese "prime minister," declares war on Syrian army in Lebanon. East Beirut besieged by Syrians and their Lebanese militia allies. Aoun abandons his war.
1990: Aoun is driven from the Presidential Palace and Lebanese civil war officially ends.
1993: Israel bombards Southern Lebanon even as Beirut is rebuilt.
July 25: Israel launches Operation Accountability in southern Lebanon.
1996: More than 200 Lebanese civilians die in Israel's "Grapes of Wrath" attack on Lebanon, 106 in a UN compound at Qana.
2000: Israel's army finally retreats behind its frontier wire as Hezbollah proclaim victory. The Oslo agreement collapses in violence.
May 25: Israel unilaterally withdraws from Lebanon.
2001: Ariel Sharon is elected Prime Minister of Israel.
From this site:
How Did We Get Here?
Note what I have bolded above. Question: What Jordanian or Palstinian authority invited Israel to occupy the West Bank?