César Antonovich Cui (Russian: Це́зарь Анто́нович Кюи́; 18 January [O.S. 6 January] 1835 – 13 March 1918) was a Russian composer and music critic of French, Polish and Lithuanian descent. His profession was as an army officer (he rose to the rank of Engineer-General (compared to full general) of The Russian Imperial Army) and a teacher of fortifications, and his avocational life has particular significance in the history of music. In this sideline he is known as a member of The Five, a group of Russian composers under the leadership of Mily Balakirev dedicated to the production of a specifically Russian type of music.