Ocko II tom Brok (1407–1435) was Chieftain of the Brokmerland and the Auricherland in East Frisia (initially under the guardianship of his grandmother, Foelke). Ocko was born in 1407 to , son of Ocko I tom Brok. He was the last East Frisian chieftain from the tom Brok line. Under his reign there was a revolt by the other Frisian chieftains against tom Brok. A conflict with his ally Focko Ukena in 1424 led to open conflict in 1426. Ocko married Ingeborg of Oldenburg, and therefore, supported by the counts, asked them for assistance. They sent an army of knights, which was defeated by Focko Ukena and his peasant army on 27 September 1426 in the Battle of Detern. On 28 October 1427, Ocko II was defeated at the and fell into captivity. He was taken to Leer and imprisoned for four years. In 14