Peter’s army had lost to Charles XII (r. 1697–1718) of Sweden at the Battle of Narva in 1700, an inauspicious beginning for Russia in the Great Northern War (1700–21). Instead of pursuing his victory over Russia, Charles deployed his forces against Poland, and gave Peter the opportunity to completely revamp his army. He ruthlessly increased taxes, built new factories, and ordered massive equipment, with all these burdens falling on one generation of Russians. In 1709, Charles’s troops were demoralized because of a harsh winter and inadequate supply lines. On July 8, at Poltava, in Ukraine, Russian troops routed the Swedes, and Russia joined the ranks of the great powers.