John Emerich Edward Dalberg Acton, 1st Baron Acton of Aldenham, 8th Baronet, known as Lord Acton, was an English Catholic Liberal historian. In 1895, he was appointed Regius Professor of Modern History at Cambridge University. Most of his written work consisted of essays and copies of his lectures. In 1899 and 1900, Lord Acton coordinated the development of The Cambridge Modern History. He served as a Member of Parliament and as an adviser and friend to Prime Minister William Gladstone. In 1865 he married Marie von Arco-Valley, with whom he had four children. He succeeded to the baronetcy in 1837, and was raised to the peerage in 1869.