Estonia (// ( listen); Estonian: Eesti ), officially the Republic of Estonia (Estonian: Eesti Vabariik), is a sovereign state in Northern Europe. It is bordered to the north by the Gulf of Finland with Finland on the other side, to the west by the Baltic Sea, to the south by Latvia (343 km), and to the east by Lake Peipus and Russia (338.6 km). Across the Baltic Sea lies Sweden in the west and Finland in the north. The territory of Estonia consists of a mainland and 2,222 islands in the Baltic Sea, covering a total area of 45,227 km2 (17,462 sq mi), water 2,839 km2 (1,096 sq mi), land area 42,388 km2 (16,366 sq mi), and is influenced by a humid continental climate. Ethnic Estonians – the largest ethnic group in country – are Finnic peoples.
The territory of Estonia has been inhabited since at least 9000 BC. Ancient Estonians were some of the last European pagans, and were Christianized during a crusade in the 13th century. After centuries of successive German, Danish, Swedish, and Russian rule, Estonians experienced a national awakening in 19th century. On 24 February 1918 independence was declared and later secured through War of Independence. After democratic rule from 1918 to 1934, Estonia became autocratic during the Era of Silence. During World War II, Estonia suffered successive occupations by Soviet Union, Nazi Germany, and Soviet Union again, resulting in its annexation as the Estonian SSR. After the loss of its de facto independence, Estonia's de jure state continuity was preserved by diplomats and government in exile. In 1987 the peaceful Singing Revolution against Soviet rule began, culminating with restoration of its de facto independence on 20 August 1991. Since restoration of its independence, Estonia has been a democratic unitary parliamentary republic divided into fifteen counties. Its capital and largest city is Tallinn. With a population of 1.3 million, it is one of the least-populous member states of the European Union, Eurozone, OECD, Schengen Area, and of NATO.
Estonia is a developed country with an advanced, high-income economy that as of 2011 is among the fastest growing in the EU. It ranks very high in the Human Development Index of the United Nations, and it performs favourably in measurements of economic freedom, civil liberties and press freedom (3rd in the world in 2012 and 2007). The 2015 PISA test places Estonian high school students 3rd in the world, behind Singapore and Japan. Citizens of Estonia are provided with universal health care, free education, and the longest-paid maternity leave in the OECD. Since independence the country has rapidly developed its IT sector, becoming one of the world's most digitally-advanced societies. In 2005 Estonia became the first nation to hold elections over the Internet, and in 2014 the first nation to provide e-residency.
In the Estonian language, the oldest known endonym of the Estonians was maarahvas, meaning "country people" or "people of the soil". The land inhabited by Estonians was called Maavald meaning "Country Realm" or "Land Realm".
One hypothesis regarding the modern name of Estonia is that it originated from the Aesti, a people described by the Roman historian Tacitus in his Germania (ca. 98 AD). The historic Aesti were allegedly Baltic people, whereas the modern Estonians are Finno-Ugric. The geographical areas between Aesti and Estonia do not match, with Aesti being farther south.