The title refers to the Estonian independence movement, incubated through the country’s stifled years as a Soviet satellite, when the sole outlet for the nation’s forbidden nationalist efforts was a folk-singing festival where tens of thousands of voices joined in a patriotic anthem. About half of The Singing Revolution recounts, through three generations of partisans, the agonized history of their pushover motherland—passed around since time immemorial between international powers—in the particularly brutal years between World War II and its 1991 declaration of independence. Singing isn’t really the focus; more important than the music (which, out of context, isn’t much) is the unity it fostered. The makers of this hugely optimistic doc, James Tusty and Maureen Castle Tusty, devote much attention to spontaneous manifestations of communal spirit. One incredible tale: As independence gains a foothold, a crowd of USSR-loyal reactionaries storms the capitol building in Tallinn. The trapped officials, lacking official police protection, radio an S.O.S. to the Estonian public—and the People actually show up, dispersing the threat in an orderly fashion. It seems an odd fit for theatrical release, but the film offers a functional primer in Baltic history, as well as choice video footage of one small country as it weathers a tectonic shift in world politics.