In the fierce struggles of the 19th century to abolish slavery, Abraham Lincoln remains the mythic American champion. In Britain, however, that honor belongs to William Wilberforce, the Christian activist and member of Parliament who thundered against the slave trade for 20 years. Friday marks the 200th anniversary of his legislative triumph — a campaign rich with lessons for modern-day reformers.

When Wilberforce first raised his voice in the House of Commons for the cause of abolition in May 1789, he spoke for 3 1/2 hours. Yet the absence of partisanship must have taken his colleagues by surprise. "I mean not to accuse anyone," he insisted, "but take the shame upon myself, in common indeed with the whole Parliament of Britain, for having suffered this horrid trade to be carried on under their authority."

Wilberforce built a human rights coalition that cut across political and ideological lines, uniting Whigs with establishment Tories and Anglicans with evangelicals and Quakers. His success, it seems, owed much to his genuine devotion to the plight of African slaves, regardless of the political costs.

A convert to evangelical Christianity, Wilberforce is greatly admired in religious circles today, if not always imitated. Early in his parliamentary career, he made a vow to avoid the corruptions of political influence — and kept it. He was known for his intellectual seriousness and personal charm. French author Madame de Stael confessed her surprise after dining with him: "I have always heard that he was the most religious, but I now find that he is the wittiest man in England."