Count Frederick of Isenberg (Friedrich von Isenberg) [1] (1193 – 15 November 1226) was a German noble, the younger son of Arnold of Altena (died 1209).[2] Before the split between Arnold of Altena-Isenberg the eldest and his brother Friedrich Altena-Mark the younger son of Everhard von Berg-Altena. His family castle was the Isenberg near Hattingen, Germany.
