Russia Declares War On Sweden (in 1700)

The Great Northern War (1700–1721) was the main military conflict of Peter the Great's reign, ending in a Russian victory over Sweden that made Russia an important European power and expanded Russia's borders to the Baltic Sea, including the site of St. Petersburg. The war began in the effort of Denmark and Poland-Saxony to wrest control of territories lost to Sweden during the seventeenth century, the period of Swedish military hegemony in northern Europe.