ACTON, JOHN EMERICH EDWARD, Lord ALDENHAM. - English politician and historian, born in Naples on 10 January 1834, died at Tegernsee (Bavaria) on 19 June 1902. He converted to Catholicism under the influence of the Archbishop of Westminster, Nicholas Wiseman, studied in Munich (from 1850) under Ranke, and there came into contact with Döllinger. Upon his return to his homeland, he served as an advisor to Gladstone in the House of Commons.
Meanwhile, he collaborated in a Catholic sense with the *English Historical Review* and then with the journal *The Rambler*, of which he took over the direction following Newman, transforming it into the *Home and Foreign Review* (from 1862). In 1869, he entered the House of Lords with the title of Baron Aldenham, and in the same year he went to Rome, where he played a decisive role, alongside Döllinger, in the movement opposing the dogma of papal infallibility. His writings on this subject (notably *The Vatican Council*, in *The North British Review*, 1870) provide an interesting documentation of the history of the First Vatican Council; however, two other works of his on the same topic were placed on the Index: *Zur Geschichte des Vaticanischen Concils* and *Sendschreiben an einen deutschen Bischof d. Vatican-Concils* (1870). Despite his stance, he did not separate from the Church, and upon his return to his homeland, he devoted himself to historical studies, among other things initiating the publication of the *Cambridge Modern History* and the *English Historical Review* (1886). From 1895 he was professor of modern history at Cambridge. After his death, the following were published from his papers: *Lectures on the French Revolution* (1906); *Historical Essays and Studies* (1907); and letters (1917), particularly interesting being those to Newman.