William Rathbone IV (10 June 1757 – 11 February 1809) was an English ship-owner and merchant involved in the organisation of American trade with Liverpool, England.
Rathbone was a committed opponent to slavery and a founding member of the Liverpool Committee for the Abolition of the Slave Trade created in 1788, a society originating in London the year before.
[2] Rathbone was considered a political radical because he supported the abolition of slavery, universal suffrage, free trade, and he was opposed to the 1793 war with France.
He would never join another religious body, though he occasionally worshipped with local Unitarian congregations.
Rathbone died on 11 February 1809 and was buried at Liverpool Friends' Burial Ground.