General Maritime Treaty of 1820

The General Maritime Treaty of 1820 was a treaty initially signed between the rulers of Abu Dhabi, Sharjah, Ajman and Umm al-Quwain and the United Kingdom in January 1820, with the nearby island state of Bahrain acceding to the treaty in the following February. Signed in Ras al Khaimah under the auspices of the UK's representative Sir William Grant-Keir, the treaty prohibited piracy in the Persian Gulf, banned slavery and required all usable ships to be registered with British forces.

The treaty was part of the UK's strategic policy of ensuring an open lines of communication between the British Raj and the United Kingdom, by excluding rival European powers from the Persian Gulf region, notably the Russian empire and France. Britain also sought to pacify the Persian Gulf by preserving the independence of Qajar Iran, the Ottoman empire and the Second Saudi State.

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