Сигизмунд Кейстутович
The Union of Grodno was a series of acts of the Polish–Lithuanian union between Kingdom of Poland and Grand Duchy of Lithuania. The first acts were signed in 1432 during the Lithuanian Civil War of 1431–1435. The acts confirmed the Union of Vilnius and Radom (1401). The Union established Sigismund Kęstutaitis as the Grand Duke of Lithuania and re-established Władysław II Jagiełło's seniority and dynastic interest in Lithuania.