The Golan Heights (Arabic: , romanized: Habatu l-Jawln or , Murtafatu l-Jawln, Hebrew: , romanized: Ramat HaGolan), or simply the Golan, is a region in the Levant spanning about 1,800 square kilometres (690 sq mi). The region defined as the Golan Heights differs between disciplines: as a geological and biogeographical region, the term refers to a basaltic plateau bordered by the Yarmouk River in the south, the Sea of Galilee and Hula Valley in the west, the Anti-Lebanon with Mount Hermon in the north and Wadi Raqqad in the east. As a geopolitical region, it refers to the border region captured from Syria by Israel during the Six-Day War of 1967; the territory has been occupied by the latter since then and was subject to a de facto Israeli annexation in 1981. This region includes the western two-thirds of the geological Golan Heights and the Israeli-occupied part of Mount Hermon.

The earliest evidence of human habitation on the Golan dates to the Upper Paleolithic period. According to the Bible, an Amorite kingdom in Bashan was conquered by the Israelites during the reign of King Og. Throughout the Biblical period, the Golan was "the focus of a power struggle between the kings of Israel and the Aramaeans who were based near modern-day Damascus." After Assyrian and Babylonian rule, the region came under the domination of Persia, following which Jews were freed from Babylonian captivity and allowed to return and resettle in the land. The Itureans, an Arab or Aramaic people, settled in the area in the 2nd century BCE and remained until the end of the Byzantine period. By the late-19th century, the Golan Heights was inhabited mostly by colonized peasants (fellan), Bedouin Arabs, Druze, Turkmen, and Circassians.In the 16th century, the Golan was conquered by the Ottoman Empire. Within Ottoman Syria, the Golan was part of the Syria Vilayet. The area later became part of the French Mandate in Syria and the State of Damascus. When the mandate terminated in 1946, it became part of the newly independent Syrian Arab Republic.

Since the Six-Day War of 1967, the western two-thirds of the Golan Heights has been occupied and administered by Israel, whereas the eastern third remains under the control of Syria. Following the war, Syria dismissed any negotiations with Israel as part of the Khartoum Resolution at the 1967 Arab League summit. Construction of Israeli settlements began in the remainder of the territory held by Israel, which was under a military administration until the Knesset passed the Golan Heights Law in 1981, which applied Israeli law to the territory; the move has been described as an annexation. The Golan Heights Law was condemned by the United Nations Security Council in Resolution 497, which stated that "the Israeli decision to impose its laws, jurisdiction, and administration in the occupied Syrian Golan Heights is null and void and without international legal effect", and Resolution 242, which emphasizes the "inadmissibility of the acquisition of territory by war". Israel maintains it has a right to retain the Golan, also citing the text of Resolution 242, which calls for "secure and recognized boundaries free from threats or acts of force".After the onset of the Syrian Civil War in 2011, control of the Syrian-administered part of the Golan Heights was split between the state government and Syrian opposition forces, with the United Nations Disengagement Observer Force (UNDOF) maintaining a 266 km2 (103 sq mi) buffer zone in between to help implement the IsraeliSyrian ceasefire across the Purple Line. From 2012 to 2018, the eastern half of the Golan Heights became a scene of repeated battles between the Syrian Army, rebel factions of the Syrian opposition (including the United States-backed Southern Front) as well as various jihadist organizations such as al-Nusra Front and the Islamic State of Iraq and the Levant-affiliated Khalid ibn al-Walid Army. In July 2018, the Syrian government regained full control over the eastern Golan Heights.On 25 March 2019, then-President of the United States Donald Trump proclaimed the recognition by the United States of the Golan Heights as part of the State of Israel, making the United States the first country to recognize Israeli rather than Syrian sovereignty over the Golan Heights. The 28 member states of the European Union declared in turn that they do not recognize Israeli sovereignty, and several experts on international law reiterated that the principle remains that land gained by either defensive or offensive wars cannot be legally annexed under international law.

The Six-Day War (Hebrew: מִלְחֶמֶת שֵׁשֶׁת הַיָּמִים, romanized: Miḥemet Šešet HaYamim; Arabic: النكسة, romanized: an-Naksah, lit. 'The Setback' or حرب 1967, Harb 1967, 'War of 1967'), also known as the June War, the 1967 Arab–Israeli War or the Third Arab–Israeli War, was an armed conflict fought from 5 to 10 June 1967 between Israel and a coalition of Arab states primarily comprising Jordan, Syria and Egypt (then known as United Arab Republic).

Relations between Israel and its Arab-majority neighbouring states were not normalized after the First Arab–Israeli War ended with the signing of the 1949 Armistice Agreements. In 1956, Israel invaded Egypt, triggering the Suez Crisis; among Israel's rationale for the invasion was its goal of forcing a reopening of the Straits of Tiran, which had been closed by Egypt for all Israeli shipping since 1950. Israel was eventually forced to withdraw its troops from Egyptian territory under international pressure, but was guaranteed that the Straits would remain open. A peacekeeping contingent known as the United Nations Emergency Force (UNEF) was subsequently deployed along the Egypt–Israel border, but there was no demilitarization agreement between the two sides.In the months prior to the outbreak of the war in June 1967, tensions in the region became dangerously heightened. Israel reiterated its post-1956 position that another closure of the Straits of Tiran to Israeli shipping by Egypt would be a definite casus belli. In May, Egyptian president Gamal Abdel Nasser announced that the Straits of Tiran would again be closed to Israeli vessels, and subsequently mobilized the Egyptian military along the border with Israel, ejecting the UNEF. On 5 June, Israel launched a series of airstrikes against Egyptian airfields, initially claiming that it had been attacked by Egypt, but later stating that the airstrikes were pre-emptive; the question of which side caused the war remains one of a number of controversies relating to the conflict.Egyptian forces were caught by surprise, and nearly the entire Egyptian Air Force was destroyed with few Israeli losses in the process, giving Israel the advantage of air supremacy. Simultaneously, the Israeli military launched a ground offensive into the Egyptian-occupied Gaza Strip and the Sinai Peninsula, which again caught the Egyptians by surprise. After some initial resistance, Nasser ordered an evacuation of the Sinai Peninsula. The Israelis continued to pursue and inflict heavy losses on the retreating Egyptian forces, and conquered the entire Sinai Peninsula by the sixth day of the war.Jordan had entered into a defence pact with Egypt a week before the war began; the agreement envisaged that in the event of a war, Jordan would not take an offensive role, but would attempt to tie down Israeli forces to prevent them from making any significant territorial gains. Approximately an hour after the initial Israeli air attack, the Egyptian commander of the Jordanian military received orders from Cairo to mount attacks against Israel. In the initially confused situation, the Jordanians were falsely informed that Egypt had successfully repelled Israel's air raids.

Egypt and Jordan agreed to a ceasefire on 8 June, and Syria agreed on 9 June; a ceasefire was signed with Israel on 11 June. In the aftermath of the war, Israel had crippled the entirety of the Egyptian, Syrian and Jordanian militaries. The war saw over 20,000 Arab troops killed while Israel lost fewer than 1,000 of its own. Israel's sweeping success was the result of a well-prepared and enacted strategy combined with the poor military and political leadership and strategy of the Arab coalition. At the cessation of hostilities, Israel had seized the Golan Heights from Syria, the West Bank (including East Jerusalem) from Jordan, and the Gaza Strip as well as the entire Sinai Peninsula from Egypt. Israel's international standing greatly improved in the years following the Six-Day War; the overwhelming Israeli victory had humiliated Egypt, Jordan, and Syria, and led Nasser to resign in shame. However, following widespread protests throughout Egypt against his resignation, he was later reinstated as president. The speed and ease of Israel's victory would later lead to dangerous overconfidence within the ranks of the Israel Defense Forces—one of the primary factors that led to initial Arab successes in the 1973 Yom Kippur War, although that war also ended in an Israeli victory. The displacement of civilian populations as a result of the Six-Day War would have long-term consequences, as around 280,000 to 325,000 Palestinians and 100,000 Syrians fled or were expelled from the West Bank and the Golan Heights, respectively.