The Baltic countries, which were absorbed by the Russian Empire between 1721 and 1795 (Estonia and Livonia in 1721, Latgale in 1772, Lithuania in 1793 and 1795, and Courland in 1795), have played a significant role in Russian economic life, and have been regarded as an important, if not a vital Russian outlet to the Baltic Sea. Before the First World War 20.6 per cent of all Russian imports and 28 per cent of all Russian exports passed through the Latvian territory alone. This was not only because Latvia is situated on the most direct trade routes between Russia and Western Europe but also because of her excellent harbors—Riga, Liepaja (Libau), and Ventspils (Windau). Three of Russia's principal railroad lines converged on these ports. In 1912 the port of St. Petersburg handled 2,500,000 tons of shipping.