Equiano had learned about the 1783 insurance claim trial related to the Zong massacre and contacted abolitionist Granville Sharp , who helped bring the case to public attention . The group held public meetings to lecture about slavery . They wrote letters , for example to the MP Sir William Dolben . They often sent letters opposing slavery and detailing conditions of the Middle Passage to newspapers , to help provoke debate . Shortly after his correspondence with them and a visit to see a slave ship being fitted out , Dolben proposed a Parliamentary bill to improve the conditions on slave ships . The Slave Act 1788 was the first law passed to regulate the slave trade , establishing standards of how many slaves could be carried in relation to ship size . Olaudah Equiano also led delegations of the Sons to Parliament to persuade MPs to abolish the international slave trade in the British colonies . This was achieved under the Slave Trade Act 1807 , which applied to all colonies except India , where slavery was part of the indigenous culture . The legislation included provisions for Britain to use naval force to enforce the law , and it began to intercept illegal slave ships off the coast of Africa . The Sons of Africa continued to work for abolition of slavery in the British colonies
Zong massacre
Zong massacre
Sons of Africa