Here is the history:
1948
Lebanon fights alongside other Arab countries against the nascent state of Israel. Around 100,000 Palestinians who fled or were expelled from their homes in what had been British-ruled Palestine during the war arrive in Lebanon as refugees. Lebanon and Israel agree to an armistice in 1949.
1968
Israeli commandos destroy a dozen passenger planes at Beirut airport in response to an attack on an Israeli airliner by Palestinian guerrillas.
The Palestine Liberation Organisation (PLO) relocates to Lebanon two years later after its expulsion from Jordan, leading to more cross-border flare-ups.
1973
Disguised Israeli special forces shoot dead three Palestinian guerrilla leaders in Beirut in retaliation for the killing of Israeli athletes at the 1972 Munich Olympics.
Palestinian guerrilla raids into Israel and Israeli military reprisals on targets in Lebanon intensify during the 1970s, leading many Lebanese to flee their country's south and aggravating sectarian tensions in Lebanon, where civil war is starting.
1978
Israel invades south Lebanon and sets up a narrow occupation zone in an operation against Palestinian guerrillas after a militant attack near Tel Aviv. Israel backs a local Christian militia called the South Lebanon Army (SLA).
1982
Israel invades Lebanon all the way to Beirut in an offensive that followed tit-for-tat border fire.
Thousands of Palestinian fighters are evacuated by sea after a bloody 10-week siege of the Lebanese capital involving heavy Israeli bombardment of West Beirut.
Hundreds of civilians in the Palestinian refugee camps of Sabra and Shatila are massacred by Christian militiamen allowed in by Israeli troops after Lebanon's newly elected Maronite Catholic president is killed by a car bomb.
Iran's Revolutionary Guards establish the Shi'ite Muslim armed group Hezbollah in Lebanon to counter the Israeli invasion.
1985
Israel pulled back from central Lebanon in 1983 but retained forces in the south. It establishes a formal occupation zone in southern Lebanon, about 15 km (nine miles) deep, controlling the area with its SLA ally. Hezbollah wages guerrilla war against Israeli forces.
1993
Israel launches in July "Operation Accountability", a week-long attack by its forces against Lebanon. Israel says the aim is to strike directly at Hezbollah, to make it difficult for the group to use southern Lebanon as a base for striking Israel, and to pressure the Lebanese government to intervene against the group.
1996
With Hezbollah regularly attacking Israeli forces in the south and firing rockets into northern Israel, Israel mounts 17-day "Operation Grapes of Wrath" offensive that kills more than 200 people in Lebanon, including 102 who die when Israel strikes a U.N. base near the south Lebanon village of Qana.
2000
Israel withdraws from southern Lebanon, after continued attacks on Israeli military positions in occupied Lebanese territory by Hezbollah, ending 22 years of occupation.
2006
In July, Hezbollah crosses the border into Israel, kidnaps two Israeli soldiers and kills others, sparking a five-week war involving heavy Israeli strikes on both Hezbollah strongholds and national infrastructure.
While Israeli ground forces move into southern Lebanon, much of the conflict is conducted by Israeli airstrikes and Hezbollah rocket fire. It ends without Israel achieving its military objectives and with Hezbollah declaring it a "divine victory".
At least 1,200 people in Lebanon, mostly civilians, and 158 Israelis, mostly soldiers, are killed.
2024
On Sept. 23, Israel launches "Operation Northern Arrows" against Hezbollah after almost a year of trading fire across the Lebanese-Israeli border in parallel with the Gaza war. The operation comes less than a week after pagers and walkie-talkies used by Hezbollah explode across Lebanon in an attack the group blames on Israel.
The violence is an escalation of cross-border warfare that started a day after the Oct. 7, 2023 attack on southern Israel by Hamas-led Palestinian militants. Hezbollah says its strikes into Israel are to support Palestinians under Israeli bombardment in the Gaza Strip.
Israel says its military goal on its northern border is to ensure the safe return of residents of northern communities to their homes. Hezbollah links its stopping of rocket attacks on Israel to a ceasefire in the Gaza war.
Israeli airstrikes intensify and pound areas of south Lebanon and the Bekaa valley and target sites in Beirut's southern suburbs and even reach the Christian-majority Keserwan district north of Beirut for the first time. Hezbollah responds with barrages of rockets fired into Israel.
Hundreds of people are killed and thousands injured in Lebanon and tens of thousands flee their homes in the south to various places across Lebanon and even to war-ravaged neighbouring Syria, sheltering mostly in schools.
