Estonia in World War II When Soviet troops marched into Estonia the guns of both nations gave mutual salutes, and bands played both the Estonian anthem and the Internationale, the anthem of the USSR, at the time. Similar demands were forwarded to Finland, Latvia and Lithuania. Finland resisted, and was attacked by the Soviet Union on November 30. Because the attack was judged as illegal, the Soviet Union was expelled from the League of Nations on December 14. Finland held out in the Winter War until March 1940, when the Moscow Peace Treaty was signed. The first population loss for Estonia was the repatriation of
Oil shale in Estonia increasing the use of other energy sources such as renewable energy and natural gas. In 2016, 73% of oil shale mined in Estonia was used for power generation, and about 90% of Estonia's electricity was generated from oil shale. About 15% of produced electricity was exported to Finland and Latvia. Eesti Energia owns the largest oil shale-fuelled power stations (Narva Power Stations) in the world. In addition, a new 300 MW station, which will use circulating fluidised bed boiler technology, is under construction in Auvere. In 2010, 11.4% of the heat supply in Estonia was generated by direct combustion of