In 1807 Parliament voted to outlaw the slave trade. Given that the booming British economy was based on the principle of free trade it was an amazing decision, taking a humanitarian stance before the need for profit. Up to four million African slaves had been transported in British ships to the New World since 1650 and at the end of the eighteenth century Britain had dominated the trade.

Banning the slave trade was one thing, but enforcing the ban was quite another. Britain possessed the largest and most powerful navy in the world and while at war with France could intercept ships under belligerent rights. However in peacetime the prevention of piracy was the only acceptable reason for boarding the ships of other nations. By exerting her political, naval and economic muscle, Britain was able to get almost thirty countries to sign a series of treaties to support her stance.

The Admiralty's main focus in the nineteenth century was on the threat posed by France and Russia, but in 1819 it established the West Coast of Africa Station, known as the 'preventive squadron', which for the next fifty years operated against the slavers. In the 1840's around twenty-five ships and 2,000 officers and men were on the station, supported by 1,000 Kroomen, native African sailors.

The ships were generally smaller types such as sloops and brigs, their shallow draught permitting them to chase vessels close to the shore. Crews were afforded relative freedom of action within their patrol area, regularly experiencing the excitement of pursuing slave ships. Action was also taken against African leaders who refused to agree treaties to outlaw slavery, for example the King of Lagos was deposed in 1851 by British forces.

Service on the West African Station was a somewhat thankless task and here the navy experienced some of its worst conditions. Boarding disease-ridden slave ships posed an obvious risk and the climate was notoriously unhealthy. The mortality rate was fifty-five per 1,000 men, compared with only ten for fleets in home waters and the Mediterranean. Some benefit could be accrued from Prize Money awarded to crews for each slave released and each ship captured, but only senior officers could expect to profit substantially.

Enforcement in East Africa and the Indian Ocean posed even more problems because for the Arabian and Persian merchants slaves were a major element of the economy. Despite the navy's best efforts, decisive political blows against the Atlantic slave trade were necessary, primarily in the United States. President Lincoln signed the Right of Search Treaty in 1862 and the Cuban trade ended four years later. One of the Royal Navy's lesser-known activities of the nineteenth century, the campaign against slavery was maintained with dedication and determination to compel compliance with Britain's moral and humanitarian stance.

Further reading:

• R.C Howell, The Royal Navy and the Slave Trade London: 1987)
• P. Padfield, Rule Britannia: The Victorian and Edwardian Navy (London: 1981)