When it comes to national sovereignty, geography is destiny. Estonia, perched on the eastern coast of the Baltic Sea, is positioned as a gateway between Europe and Russia, which has made the small country a doormat for invaders and a reluctant host for parasitic occupiers for centuries. James Tusty and Maureen Castle Tusty’s “The Singing Revolution” documents the last 100 years of Estonia’s misery under Nazi occupation and Soviet rule, a period of social-political malfeasance so barbarous that the country’s identity was nearly extinguished.

Having endured German crusaders and Danish and Swedish occupation in the Middle Ages, Estonia finally took the first steps toward its own identity in the late 19th century. Part of the country’s nationalist “great awakening” was the Laulupidu, an enormous outdoor music festival in which thousands would commune through group singing. In the aftermath of World War I, Estonia finally established itself as a self-governing entity. But when Nazi and Soviet negotiators met to hammer out the infamous Molotov-Ribbentrop Pact of 1939, Estonia was ceded to the USSR, which promptly sent some 25,000 troops to once again occupy the hard-luck Baltic state. When Stalin and Hitler fell out, the Nazis overran the country and replaced the Soviets’ systematic murder and deportation of Estonian nationals with mandatory conscription of the conquered nation’s youth into the German army. By the end of World War II, Estonia was back in Stalin’s hands and remained under Soviet control all through the Cold War.

The Soviets imported thousands of Russian nationals into the country and outlawed any acknowledgment of Estonia’s nationhood. Under Stalin, the Laulupidu was transformed from a celebration of native culture into a mass singing of patriotic Soviet songs. “Patience is a weapon,” according to Baltic wisdom. Despite Soviet efforts to bleach the patriotism out of the Laulupidu gathering, the group singing became a kind of periodic (since it took place only twice a decade) and potent underground recommitment to the idea of Estonian emancipation. Thanks to the language gap, (the Estonian dialect is closer to Finnish than to Russian), in 1969 a defiant group of 30,000 protesters were able to perform the nation’s unofficial national anthem before Soviet authorities could shut them down. During the subsequent decades leading up to Mikhail Gorbachev’s lessening of free speech restrictions under glasnost, the spirit of that performance remained alive in every gathering that followed.

As an example of cut-and-dried journalistic documentary filmmaking, “The Singing Revolution,” which makes its premiere today, is unremarkable. Vintage clips of Soviet mass executions are suitably gruesome; aerial views of Laulupidu performances are suitably spectacular, and video news footage of unarmed Estonians manning the barricades against approaching Soviet tanks in the final years of Communist rule is suitably inspiring in the usual armchair cable TV historian way. What makes the “The Singing Revolution” compelling is the first-person accounts of a dozen or more individual patriots who describe their sacrifices in Siberian gulags and at home with the matter-of-fact ease of those whose conviction never wavered. “I did not cry because it was so unreal,” one woman says of her deportation to a Soviet slave labor camp at age 14. But with voices and faces attached, her fellow citizens’ bravery becomes very real. “Gorbachev made one very, very basic fundamental mistake,” offers one Estonian activist. “Whenever you give free speech to people, then things get out of hand. The ghost gets out of the bottle.”

In Communist-ruled Estonia, that freedom of speech was best expressed in song. “It may sound today a bit silly, it may sound even naïve,” recalls a veteran of the final Laulupidus before Estonia achieved sovereignty. “In those days it was so natural to express our feelings by singing and declaring that we have a right to our own country.” For Westerners accustomed to flouting or abusing democratic freedoms, the story of “The Singing Revolution” is a thought-provoking reminder that culture and citizenship are closer bedfellows than we might realize, and that having a song in one’s heart is more than just a romantic notion.