István was the son of Farkas Bánffy de Losoncz and Klára Bethlen de Bethlen. The date and place of his birth have not been found.
His wife was Katalin Károlyi de Nagykároly. They were married, but the date and place have not been found. They had no known children.
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Klára Bethlen de Bethlen |
Gergely Bethlen de Bethlen |
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