When I toured Westminister Abbey some decades ago, I recall seeing the tomb, or at any rate the name, of William Wilberforce. The name was familiar, so I asked the guide (docent?) if he was related to that Bishop Samuel Wilberforce who had famously debated Thomas Huxley on evolution. William was indeed the father of that Bishop, but if I learned what he had done to earn his place amongst England's great heroes I don't recall it.
What he did was lead the long crusade in England to ban the slave trade. The movie Amazing Grace is a lightly fictionalized account of that crusade, and to me a great movie. Gorgeous English scenery, a dramatic true story, and, best of all, a whole potfull of great British actors - Ioan Gruffudd, Benedict Cumberbatch, Albert Finney, and Michael Gambon to mention a few.
He and his cohorts changed the world for the better, a great deed indeed. Moreover he did it by doing good - not by starting a war but by making the world see evil through his eyes.
When looking up the story of his third son, Bishop Samuel Wilberforce, I was quite charmed to read that after the debate with Huxley, both sides went out for a convivial evening of food and fellowship.