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In page Gertrude of Hohenberg:

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Gertrude was born in Deilingen, Swabia[citation needed] to Count Burkhard V of Hohenberg (died 1253) and his wife Matilda (Mechtild),[1] daughter of Count Palatine Rudolf II of Tübingen. The comital Hohenberg dynasty, a cadet branch of the Swabian House of Hohenzollern, then ruled over extended estates in southwestern Germany. Citing contemporary sources, Gertrude's descent was questioned by the Swiss historian Aegidius Tschudi (1505–1572), who postulated a Frohburg lineage; nevertheless, his objections have been disproved.