Flag of Mandatory Palestine

During the British Mandate over Palestine between 1920 and 1948, the de facto flag was the Union Jack or Union Flag of the United Kingdom, but several localised flags existed for Mandate government departments and government officials. The only Palestine-specific flag not restricted to official government use was the Palestine ensign (red with the Union Flag in the canton, and a white circle on the fly with the mandate's name inside it), which was flown by ships registered in the British Mandate territory from 1927 to 1948. This flag had an extremely limited use on land and was not embraced by either the Arabs or the Jews of the Palestine mandate territory. It was based on the British Red Ensign (civil ensign) instead of the Blue Ensign (used as the basis for the flags of nearly all other British-ruled territories in Africa and Asia) since it was intended for use only at sea by non-government ships.

Palestinian Arabs sometimes flew their own flags, often variations of the Flag of the Arab Revolt. In 1929, a discussion was held for a Palestinian national flag and the newspaper Filastin published on its front page a proposal to establish a Palestinian national flag and anthem. Various different flags were proposed, they were mainly based off the Flag of the Arab Revolt but also included the use of crosses with crescents and the color orange. During the 1936–39 Arab revolt in Palestine a group was photographed with a flag similar to the current Palestinian flag but with a crescent and cross as well as Arabic inscription.

Flag of the Arab Revolt, many Palestinian nationalist flags were based off this.

The use of Zionist or was common in the Yishuv, as the body of Jewish residents in Palestine was known before the establishment of the State of Israel, and such flags were often flown by such Yishuv institutions as The Jewish Agency or the Histadrut. However, the Yishuv constituted only one of the country's main ethnic communities - the other such community, the Palestinian Arabs, being opposed to the Zionist movement and to this movement's flag(s). Thus, Hebrew flags were never recognized or given an official status by the British authorities, which throughout the vicittudes of their Palestine policy always asserted an impartiality as between Jews and Arabs - the only official Flag of Palestine being the Union Jack and its derivatives, as noted above.

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