In May 1967, Egyptian President Gamal Abdel Nasser moved his forces into the Sinai Peninsula, close to the Israeli border. Facing Arab nations' pressure and heightened expectations of Arab military strength, Nasser requested the withdrawal of the United Nations Emergency Force (UNEF) from Egypt's border with Israel in Sinai on 18 May 1967. Subsequently, Egypt blocked Israeli access to the Straits of Tiran, a move Israel considered an act of war. On 30 May, King Hussein of Jordan and Nasser signed a Jordanian-Egyptian defense pact.

Egypt initially planned an attack on Israel for 27 May but canceled it at the last moment. On 5 June, Israel launched a preemptive strike against Egypt, severely damaging Egyptian airfields and largely destroying their air force. This action led to Israel's occupation of the Sinai Peninsula and the Gaza Strip. Jordan and Syria, siding with Egypt, entered the war but faced Israeli occupation of the West Bank and the Golan Heights. A ceasefire, mediated by the UN Security Council, was accepted by Egypt, Jordan, and Syria between 7 and 10 June.

The defeat in the 1967 War led Nasser to resign on 9 June, nominating Vice-President Zakaria Mohieddin as his successor. However, Nasser withdrew his resignation following widespread public demonstrations supporting him. Post-war, seven senior military officers, including Minister of War Shams Badran, were tried. Field-Marshal Abdel-Hakim Amer, the armed forces' Commander-in-Chief, was arrested and reportedly committed suicide in custody in August.