Thomas Babington Macaulay, the leading Whig historian, was in parliament for Calne, Leeds and Edinburgh between 1830 and 1856, and rose to become the secretary of state for war and paymaster general. His nephew G O Trevelyan wrote The Life and Letters of Lord Macaulay and was himself an MP for Tynemouth, Hawick and Glasgow Bridgeton between 1865 and 1897.
Lord Acton (who coined the phrase "Power tends to corrupt, absolute power corrupts absolutely", as well as "Socialism leads to slavery") represented the Irish seat of Carlow from 1859 until 1865, when he was elected for Bridgnorth but was not allowed to take his seat. H A L, or Herbert, Fisher (A History of Europe) was Sheffield Hallam's first ever Liberal MP between 1916 and 1918 - its last for 79 years. He moved to the Combined English Universities seat for the following eight years (beating Labour's Leonard Woolf in 1922), and his 1918 education act raised the school-leaving age to 14.