The Battle of Lappeenranta in 1741 marked Finland’s fiery entry into the Russo-Swedish War — where a border fortress fell under Russian assault in the conflict later remembered as the “War of the Hats.” August 23, 1741. Summer heat hung over the wooden fortifications of Lappeenranta in southeastern Finland. Sweden, eager to reclaim prestige lost to Russia in earlier wars, had declared conflict — a decision driven by political factions known as the “Hats.” Finland, then part of the Swedish realm,