of Roskilde, a treaty very favorable to the Swedish. During the Great Northern War, Swedish king Charles XII set off to invade Moscow, but was eventually defeated at the Battle of Poltava after being weakened by cold weather and scorched earth tactics. Sweden suffered more casualties during the same war as Carl Gustaf Armfeldt with 6,000 men tried to invade Trondheim. Three thousand of them died of exposure in the snow during the Carolean Death March. 19th century During the Finnish War, the Russian army unexpectedly crossed the frozen Gulf of Bothnia from Finland to Åland and, by 19 March 1809, reached the Swedish shore within from the Swedish capital, Stockholm. This daring maneuvre decided the outcome of the war. Napoleon's invasion of Russia in 1812 resulted in retreat in the face of winter with the majority of the French army succumbing to frostbite and starvation, rather than combat injuries. The Battle of Weihaiwei was a battle of the First Sino-Japanese War in the winter of 1895 in Weihai, Shandong, China between the forces of the Japan and Qing China. Through a well coordinated offensive of both naval and land forces, hampered by snow and cold, the Japanese destroyed the forts on shore and sank much of the Chinese fleet. 20th century World War I During the First World War, soldiers on the Western front involved in trench warfare were forced to deal with freezing conditions, trench foot, frostbite, and disease. The winter of 1916-17 was exceptionally cold, which caused great hardship and deaths among the soldiers. Equipment and vehicles also were not suited for the freezing conditions. At the Battle of Sarikamish, Ottoman troops were unprepared for winter fighting and suffered major losses, with 25,000 freezing to death before the battle even began. On the Italian front, fighting bogged down in trench warfare but at mountain elevations. On White Friday, thousands of troops from both sides were killed in avalanches in the Dolomites. World War II The Finnish Army used ski troops during the Winter War and the Second World War in which the numerically-superior but road-bound Soviet forces were vulnerable to attack by mobile, white-clad ski troops, approaching from untracked, frozen terrain. The Wehrmacht maintained elite mountain troops, Gebirgsjäger. They were organized in small, specialized units, which relied on pack animals. Typical weapons were light machine guns, mortars, and anti-tank guns. Control of ridge lines was paramount, using