In the West Indies, Ramsay witnessed and was shocked by the cruelty inflicted upon the enslaved Africans and campaigned against the owners and planters who were largely responsible.
Other significant campaigners who became part of the Teston circle were Hannah More, philanthropist and writer; anti-slavery campaigner Beilby Porteus, Bishop of Chester, who also held the living of the nearby village of Hunton, Kent and had been influenced by Ramsay's writings; as well as Middleton and his wife Margaret (née Gambier), Lady Middleton.
Their activism was instrumental in "channel[ing] the reform currents that shaped the cultural landscape in Britain",[1] and, through the influence they exerted on such men as Thomas Clarkson, they were indirectly responsible for the founding of the Society for Effecting the Abolition of the Slave Trade in May 1787.
Clarkson had pledged his energies to a national campaign for slave trade abolition in the autumn of the previous year.
He later went on to steer through Parliament the legislation that finally led, almost twenty years later, to the passage of the Slave Trade Act in 1807.