Reinhold Moritzevich Glière (Russian: Ре́йнгольд Мо́рицевич Гли́эр / Reingol'd Moritsevich Glier; born Reinhold Ernest Glier, which was later converted for standardization purposes; 11 January 1875[O.S. 30 December 1874]–23 June 1956) was a Russian composer of German-Polish ancestry.