Frederick of Isenberg (b. 1193)
Count Frederick of Isenberg (Friedrich von Isenberg) (1193 – 15 November 1226) was a German noble, the younger son of Count (died 1209). Before the split between Arnold of Altena-Isenberg the eldest and his brother Friedrich Altena-Mark the younger son of Everhard von Berg-Altena. In those day's the ‘Grafschaft Mark’ not yet exist, there is no doubt about that! His family castle was the Isenberg near Hattingen, Germany.