- (1672–1725), tsar of Russia 1682–1725; known as Peter the Great. Peter modernized his armed forces before waging the Great Northern War (1700–21) and expanding his territory in the Baltic. His extensive administrative reforms were instrumental in transforming Russia into a significant European power. In 1703 he made the new city of St Petersburg his capital.
More definitions of Peter IDefinition of Peter I in:
- The US English dictionary