[2] A number of the founders had been meeting at George Yard since 1783, and over four years grew their circle of friends to include Thomas Clarkson, an unknown at that time.

They were also influenced by the publicity that year about the Zong massacre, as the shipowners were litigating a claim for insurance against losses due to more than 132 slaves having been killed on their ship.

[citation needed] "In 1787, approximately three-quarters of the people on Earth lived under some form of enslavement, serfdom, debt bondage or indentured servitude.

"[3] The Quakers decided to form a small, committed, non-denominational group so as to gain greater Church of England and Parliamentary support.

[5] The reverberations from what happened on this spot, on the late afternoon of 22 May 1787, eventually caught the attention of millions of people around the world, including the first and greatest student of what today we call civil society.

The result of the series of events begun that afternoon in London, wrote French political philosopher Alexis de Tocqueville decades later, was "absolutely without precedent...If you pore over the histories of all peoples, I doubt that you will find anything more extraordinary".

They formed themselves into a committee with what seemed to their fellow Londoners a hopelessly idealistic and impractical aim: ending first the slave trade and then slavery itself in the most powerful empire on Earth."

Three Anglicans were founding members: The society did not aim at ending slavery altogether, but only to abolish British involvement in the international slave trade.

The society's methods for pursuing its goals included writing and publishing anti-slavery books, abolitionist prints, posters and pamphlets, and organising lecture tours in the towns and cities of England.

At length the taste for wearing them became general, and thus fashion, which usually confines itself to worthless things, was seen for once in the honourable office of promoting the cause of justice, humanity and freedom".

[4] As Wilberforce continued to bring the issue of the slave trade before Parliament, Clarkson and others on the Committee travelled, raised funds, lobbied, and wrote anti-slavery works.

Across the whole society, female subscribers comprised about 10 per cent of the membership, while in some centres, notably Manchester (with 68 women, or nearly a quarter of the total), the percentage was higher.

[7] Several members of the society also subscribed to the African Institution (founded 1807 to create a viable, civilised refuge for freed slaves in Sierra Leone[16]).

[citation needed] Petitioning peaked in 1792, with up to 100,000 signatures (Manchester alone contributed 10,639), and regional anti-slavery groups started taking the lead, especially in the north of England.

When the Royal Navy later intercepted illegal slave trading ships, its crews frequently resettled the liberated Africans at Freetown.

Such supporters sometimes provided refuge to Americans who had escaped from slavery and helped raise money to buy their freedom, as for Frederick Douglass.