Kazimierz Leon Sapieha (Lithuanian: Kazimieras Leonas Sapiega) (1609–1656)[1] was a nobleman of the Grand Duchy of Lithuania, a part of the Polish–Lithuanian Commonwealth, Royal Secretary[2] and Grand Writer of Lithuania from 1631,[3] Court Marshal of Lithuania from 1637, Deputy Chancellor of Lithuania from 1645.[4]
Son of Lew Sapieha.[5] He studied abroad in Munich and Ingolstadt.[6] Sejm deputy in 1631. One of four executors of Władysław IV Waza's last will. Opponent of Janusz Radziwiłł; organized anti-Swedish resistance in Lithuania during The Deluge.