How did William Wilberforce meet Thomas Clarkson?

Answer 1

Thomas met William Wilberforce when in 1787 when he showed him his essay on slavery, to have him join his campaign. An illustration in the movie 'Amazing Grace (2006)' suggests that he first met him in William Wilberforce's estate.

Source:

http://abolition.e2bn.org/people_24.html

Amazing Grace (2006) film

Answer 2

William Wilberforce first met Thomas Clarkson in 1787 when they both attended a meeting of the Committee for the Abolition of the Slave Trade. Wilberforce had recently become interested in the abolitionist cause, and Clarkson had already been campaigning against slavery for several years. Their shared commitment to ending the slave trade and their complementary skills and knowledge led to a close collaboration and friendship that lasted for decades.