Complex sentence: The Hungarian tradition preferred agnatic seniority "(senioratus)" which gave preference to the oldest patrilineal member of the royal family, while the Christian tradition supported the principle of primogeniture pursuant to which the eldest son of the deceased king inherited the throne.
Split into simpler sentences: The Hungarian tradition preferred agnatic seniority "(senioratus)", which gave preference to the oldest patrilineal member of the royal family. Meanwhile, the Christian tradition supported the principle of primogeniture, pursuant to which, the eldest son of the deceased king inherited the throne.