ENNEN, LEONHARD. – Priest and historian, born in Schleiden on 5 March 1820, died in Cologne on 14 June 1880. He was one of the founders of the Historisches Verein für den Niederrhein. He was chiefly interested in the history of the city and diocese of Cologne.
He wrote a history of the Reformation within the diocese (Geschichte der Reformation im Bereiche der alten Erzdiözese Köln, Cologne 1849), a five-volume history of Cologne (Geschichte der Stadt Köln, there 1865–86), and collected documents on the history of the city, a series which in 6 vols. reaches as far as 1397 (Quellen zur Geschichte der Stadt Köln, there 1860–79).
BIBL.: H. Knippen, s. V. in Allgemeine Deutsche Biographie, XLVIII, pp. 380–82. Silvio Furlani