The Great Northern Expedition (Russian: Великая Северная экспедиция) or Second Kamchatka Expedition (Russian: Вторая Камчатская экспедиция) was a major Russian Arctic expedition between roughly 1733 and 1743, which mapped most of the Arctic coast of Siberia and much of the Arctic coast of North America, greatly reducing "white areas" on maps. It was conceived by Russian emperor Peter the Great, and took place under empresses Anna and Elizabeth. Peter hoped for the 18th-century Russian Navy to map a Northern Sea Route from Europe to the Pacific. The endeavour was sponsored by the Admiralty College in Saint Petersburg. The main organiser and leader of the expedition was Vitus Bering, who had been commissioned by Peter to lead the earlier First Kamchatka Expedition (1725 to 1731). With over 3,000 people directly or indirectly involved, it was one of the largest expeditions in history.
The expedition's primary objective was reaching the eastern reaches of Siberia, and from there the western shores of North America. The expedition included the European discovery of Alaska, the Aleutian Islands, the Commander Islands, and Bering Island—as well as a detailed cartographic assessment of the northern and north-eastern coast of Russia and the Kuril Islands. Any large landmass in the North Pacific, as well as any economically viable Northeast Passage sought since the 16th century, were both proven not to exist. Other findings included ethnographic, historic, and scientific research into Siberia and Kamchatka. Its cost was an estimated 1.5 million rubles, financed entirely by the Russian state, equal to roughly one-sixth of state income in 1724.
