Sweden, formally the Kingdom of Sweden, is a Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At 450,295 square kilometres (173,860 sq mi), Sweden is the largest Nordic country and the fifth-largest country in Europe. The capital and largest city is Stockholm. Sweden has a population of 10.5 million, and a low population density of 25.5 inhabitants per square kilometre (66/sq mi); around 87% of Swedes reside in urban areas in the central and southern half of the country. Sweden’s urban areas together cover 1.5% of its land area. Because the country is so long, ranging from 55°N to 69°N, the climate of Sweden is diverse.

Sweden has been inhabited since prehistoric times, c. 12,000 BC. The inhabitants emerged into history as the Geats (Swedish: Götar) and Swedes (Svear), which together constituted the sea-faring peoples known as the Norsemen. A unified Swedish state was established during the late 10th century. In 1397, Sweden joined Norway and Denmark to form the Scandinavian Kalmar Union, which Sweden left in 1523. When Sweden became involved in the Thirty Years' War on the Protestant side, an expansion of its territories began, forming the Swedish Empire, which remained one of the great powers of Europe until the early 18th century. During this era Sweden controlled much of the Baltic Sea. Most of the conquered territories outside the Scandinavian Peninsula were lost during the 18th and 19th centuries. The eastern half of Sweden, present-day Finland, was lost to Imperial Russia in 1809. The last war in which Sweden was directly involved was in 1814, when Sweden by military means forced Norway into a personal union, a union which lasted until 1905.

Sweden is a highly developed country ranked fifth in the Human Development Index. It is a constitutional monarchy and a parliamentary democracy, with legislative power vested in the 349-member unicameral Riksdag. It is a unitary state, divided into 21 counties and 290 municipalities. Sweden maintains a Nordic social welfare system that provides universal health care and tertiary education for its citizens. It has the world's 14th highest GDP per capita and ranks very highly in quality of life, health, education, protection of civil liberties, economic competitiveness, income equality, gender equality and prosperity. Sweden joined the European Union on 1 January 1995. It is also a member of the United Nations, NATO, the Nordic Council, the Schengen Area, the Council of Europe, the World Trade Organization and the Organisation for Economic Co-operation and Development (OECD).