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in the Polish-Lithuanian Commonwealth between the 16th and 18th centuries, the Sejm convoked by the archbishop of Gniezno (the primate of Poland) upon the death of the king. During the interregnum the archbishop fulfilled the king’s functions and was called the interrex. The Sejm was responsible for ensuring law and order until a successor was chosen, and it determined the date and made preparations for the election of a new king, which took place at the Electoral Sejm. The Convocation Sejm constituted a confederation, thus precluding use of the liberum veto and the Sejm’s breakup.