The Full Story
In 1822, Captain Fairfax Moresby negotiated a treaty with the Sultan of Muscat that would change the Indian Ocean forever. The Moresby Treaty established a line. Cross it with enslaved people, and the British Navy would seize your ship.
The line ran from Cape Delgado in Mozambique, the southern tip of the Sultan's African territory, across the Indian Ocean to Diu on the coast of India. Any dhow carrying enslaved people beyond it could be captured, the people aboard freed, and its crew detained.
For decades afterwards, British warships patrolled this line. Dhows were stopped, searched, and when found carrying human cargo, seized. The enslaved people on board were landed at places including the Seychelles and Bombay, where they were freed.
The line stayed. It did not end the Indian Ocean trade by itself, but it was the first step in 75 years of British pressure that ended with Zanzibar's abolition decree of 1897.
Why This Matters
The Moresby Treaty shows the global reach of British abolition efforts. This wasn't just about the Atlantic. Britain fought to end slavery across the Indian Ocean too.
Key Facts
- ⚠Correction: the video describes the line as running roughly along the 55th meridian to the Laccadive Islands; the verified line ran from Cape Delgado in Mozambique to Diu on the coast of India (Wikipedia Moresby Treaty, Britannica). The treaty's initial effect on the trade was also limited; it was the first step in 75 years of pressure, not an immediate collapse.