János was the son of András Forgách de Ghymes et Gács but his mother is unknown. The date and place of his birth have not been found.
János Forgách de Ghymes et Gács
András Forgách de Ghymes et Gács
Miklós Forgács de Koszmál et Gimes (-<1333)
András Forgáchs (-1312)
Anna Csetneki
Benedek Csetneki (c1250-?)
Zsuzsanna de Keselkeő