Greater Finland

Greater Finland (Finnish: Suur-Suomi; Swedish: Storfinland) is an irredentist and nationalist idea that emphasized territorial expansion of Finland. The most common conception of Greater Finland was defined by natural borders encompassing the territories inhabited by Finns and Karelians, ranging from the White Sea to Lake Onega and along the Svir River and Neva River—or, more modestly, the Sestra River—to the Gulf of Finland. Some proponents also included the Kola Peninsula (as part of a natural border), Finnmark (in Norway), Torne Valley (in Sweden), Ingria (around present-day Saint Petersburg), and Estonia.

The idea of Greater Finland gained popularity and influence rapidly in 1917, but lost support after World War II and the Continuation War.

The idea of the so-called three-isthmus border—defined by the White Isthmus, the Olonets Isthmus, and the Karelian Isthmus—is hundreds of years old, dating back to the period when Finland was part of Sweden. There was a disagreement between Sweden and Russia as to where the border between the two countries should be. The Swedish government considered a three-isthmus border to be the easiest to defend.

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