The 17th century brought a number of setbacks. The Commonwealth was involved in a series of wars, collectively known as The Deluge. During the Thirteen Years' War (1654–1667), Vilnius was occupied by Muscovite forces; it was pillaged and burned, and its population massacred. During the Great Northern War it was looted by the Swedish army. An outbreak of bubonic plague in 1710 killed about 35,000 residents; devastating fires occurred in 1715, 1737, 1741, 1748, and 1749. The city's growth lost its momentum for many years, but even despite this fact, at the end of the 18th century and before the Napoleon wars, Vilnius, with 56,000 inhabitants, entered the Russian Empire as its third-largest city.