Despite its northerly location, Estonia enjoys a mild climate because of marine influences. Mainly a lowland, the republic has numerous lakes, frequently of glacial origin; Peipus (Lake Chudskoye), the largest, is important for both shipping and fishing. Along Estonia's Baltic coast are more than 800 islands, of which Saaremaa is the most notable. The republic's rivers include the Narva, Pärnu, Ema, and Kasari.
Estonians, who are ethnically and linguistically close to the Finns, make up about 68% of the population; Russians constitute some 25%, and there are Ukrainian, Belarusian, and Finnish minorities. Estonian is the official language, but Russian, Latvian, and Lithuanian are also spoken. The majority of those practicing a religious faith belong to either the Evangelical Lutheran or the Russian Orthodox church. There are small minorities of other Christians, but most of the population is unaffiliated. Since independence (1991), citizenship has generally been limited to ethnic Estonians, a practice widely criticized because it denies political and civil rights to the many Russian-speaking inhabitants. In 1993 ethnic Russians were officially declared foreigners, raising even stronger objections. Long-term non-Estonian residents can become citizens, but the government has limited the number that can do so annually.