This past Sunday a UU sermon described Thomas Jefferson as “the only Unitarian president or prime minister.” Actually, there have been quite a few, though it’s understandable that this may not be common knowledge. There have been five different American presidents who were Unitarians: John Adams, Thomas Jefferson, John Quincy Adams, Millard Fillmore, and William Howard Taft.
There are also two honorable mentions worth bringing up. Abraham Lincoln was influenced by the popular Unitarian preacher Theodore Parker and had positive interactions with the Universalists. And Barack Obama attended Unitarian-Universalist Sunday school as a child. Neither was/is a full-fledged Unitarian, Universalist, or Unitarian-Universalist, however.
Among the American vice presidents, John Calhoun was a Unitarian. Of course, John Adams, Thomas Jefferson, and Millard Fillmore also served as vice president in their time.
In Canada, there has been one Prime Minister, Sir Francis Hincks, who was a Unitarian. Actually, Hincks was technically a Premier, since this was before final confederation, though many historians consider the premiers to be the equivalent in all but name, since they held similar responsibilities and led directly to the prime minister’s post in 1867.
In the wider world, British Prime Minister Neville Chamberlain was raised Unitarian, though it is unclear if he considered himself Unitarian as an adult. In New Zealand, Prime Minister Robert Stout was a Unitarian.