In what year did Lord Acton say absolute power corrupts absolutely?

This arose as a quotation by John Emerich Edward Dalberg Acton, first Baron Acton (1834-1902). The historian and moralist, who was otherwise known simply as Lord Acton, expressed this opinion in a letter to Bishop ManDELL Creighton in 1887: "Power tends to corrupt, and absolute power corrupts absolutely. Great men are almost always bad men."

Another answer

William Pitt, Earl of Chatham, expressed that thought in a speech in 1770. The poet Percy Bysshe Shelly expressed it in Queen Mab, 1813. But the most usual and best-known attribution is to Lord Acton (John Emerich Dalberg-Acton), who wrote, in a letter to Bishop ManDELL Creighton (April 5, 1887), "Power tends to corrupt and absolute power corrupts absolutely."