Dubai, also spelt Dubayy, constituent emirate of the United Arab Emirates (formerly Trucial States or Trucial Oman). The second most populous and second largest state of the federation (area 1,510 square miles [3,900 square km]), it is roughly rectangular, with a frontage of about 45 miles (72 km) on the Persian Gulf. The emirate’s capital, also named Dubai, is the largest city of the federation. The city is located on a small creek in the northeast part of the state. More than nine-tenths of the emirate’s population lives in the capital and nearby built-up sections. Dubai is surrounded by Abu Dhabi Emirate on the south and west and by Sharjah emirate on the east and northeast. In addition, the small exclave (detached section) of Al-Ḥajarayn in the Wadi Ḥattā, more than 25 miles (40 km) from the nearest territory of Dubai proper, belongs to the state.
The settlement of Dubai town is known from 1799. The sheikh (Arabic: shaykh) of the emirate, then a minor, signed the British-sponsored General Treaty of Peace (1820), but the area was seemingly dependent on Abu Dhabi until 1833. In that year a group of Āl Bū Falāsah clansmen of the Banū Yās confederation, chiefly pearl fishers, left Abu Dhabi in a rivalry dispute and took over Dubai town without resistance. From then on, Dubai became, by local standards, a powerful state. It was frequently at odds with Abu Dhabi’s rulers and the Qawāsim (Āl Qāsimī), who controlled the area just north of Dubai, both of whom tried to take control of it, but Dubai’s new rulers retained their independence by playing the neighbouring sheikhdoms against each other. Together with the rest of the original Trucial States, the emirate signed with Britain a maritime truce in 1835 and the Perpetual Maritime Truce in 1853. Its foreign relations were placed under British control by the Exclusive Agreement of 1892. When Britain finally left the Persian Gulf in 1971, Dubai was a prominent founding member of the United Arab Emirates.