Estonian animation: Toell the Great (+English & Russian subtitles) 1980
1980 mythical Estonian animation by Rein Raamat. Perhaps not for children. Do read the original story, because the film may be confusing: http://niffiwan.livejournal.com/5860.html
Toell was a hero who lived on the island of Saaremaa. He was not a warrior by nature, but he had to fight enemies who attacked the island from outside, as well as the Old Vile One who lived on the island itself. This was actually shown on television in the Soviet Union, not just in Estonia, and many children saw it. A lot of the comments I've seen say that this film gave them nightmares. Translation from Estonian is by elephant (aka. Heinrich Sepp, 2007-09-30). He adds: "Most of the chanting, consists of a small wordplay and repetition of words. The choir starts off with 'Tõll' and continues with 'tuul' (wind), then 'tuur' (tour) and finally 'suur' (big)." From myself, I'll add that during the battle scenes the choir seems to be chanting 'vaenlane' (enemy). This film is also known as "Tyll the Giant"