The flag of Palestine (علم فلسطين) is a tricolor of three equal horizontal stripes (black, white, and green from top to bottom) overlaid by a red triangle issuing from the hoist. This flag is derived from the Pan-Arab colors and is used to represent the State of Palestine and the Palestinian people. It was first adopted on 28 May 1964 by the Palestinian Liberation Organization. The flag day is celebrated on 30 September.
The flag is similar to that of Syria's Ba'ath Party, which uses the same shapes and colours but a 2:3 ratio as opposed to Palestine's 1:2, as well as the short-lived Arab Federation of Iraq and Jordan (which had an equilateral triangle at the hoist). It is also very similar to the Flag of Jordan and to the Flag of Western Sahara, all of which draw their inspiration from the Arab Revolt against Ottoman rule (1916–1918). The flag of the Arab Revolt had the same graphic form, but the colours were arranged differently (white on the bottom, rather than in the middle).
In 2021, President Mahmoud Abbas approved the annual lowering of the flag to lament the Balfour Declaration.
The flag used by the Arab Palestinian nationalists in the first half of the 20th century is the flag of the 1916 Arab Revolt. The origins of the flag are the subject of dispute and mythology. In one version, the colours were chosen by the Arab nationalist 'Literary Club' in Istanbul in 1909, based on the words of the 13th-century Arab poet Safi al-Din al-Hili:
Ask the high rising spears, of our aspirations
Bring witness the swords, did we lose hope
We are a band, honor halts our souls
Of beginning with harm, those who won't harm us
White are our deeds, black are our battles,
Green are our fields, red are our swords.
Another version credits the Young Arab Society, which was formed in Paris in 1911. Yet another version is that the flag was designed by Sir Mark Sykes of the British Foreign Office. Whatever the correct story, the flag was used by Sharif Hussein by 1917 at the latest and quickly became regarded as the flag of the Arab national movement in the Mashriq.