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Plenimir (Bulgarian: Пленимир) was a Bulgarian prince (knyaz), the son of emperor (tsar) Peter I (r. 927–969). He was one of three sons of Peter I, all born between 931 and 944. Historiography is well-informed on his two brothers, Boris II and Roman, while scarce information exist on Plenimir. His brothers reigned as Bulgarian tsars Boris II (r. 969–971) and Roman (r. 977–991).