vertically divided white-maroon national flag. Its width-to-length ratio is 11 to 28.

The Ottoman Empire, Iran, and Britain all had an interest in finding allies among the small Arab sheikhdoms in the Persian Gulf during the 19th century. A treaty signed in 1868 between Britain and one of those states, Qatar, may have been the occasion for the creation of the distinctive Qatari flag. Later the Turkish flag (Turkey, flag of) flew there, but during World War I, when the United Kingdom and the Ottoman Empire were enemies, the British again moved to preserve sovereignty for Qatar under British protection. The Union Jack (United Kingdom, flag of the) was not flown, except by the local British representative.

At first the flag of Qatar did not have a precisely defined design. Like many other flags in the area, it consisted of two colours, with variations in the exact configuration according to the taste of the maker. Qatar chose mauve or maroon instead of the more typical red for its flag, perhaps to distinguish it from the similar flag used in neighbouring Bahrain or because local natural dyes tended to darken in sunlight. The name of the country in white Arabic script was sometimes added, and the dividing line between the colours could be straight or serrated. In the latter case there were sometimes small maroon diamonds in the white area between the serration teeth. Inscriptions have long been popular on Arab flags because the Islamic faith forbids the representation of living beings and indirectly encourages calligraphy by the emphasis placed on the reading of the Qurʾān. No change was made in the Qatari flag at the time of independence on September 1, 1971.