Alouette! is an old French song, but its greatest popularity is in French Canada.

Marius Barbeau- "Cette rengaine, née en France, est devenue la plus populaire de toutes les chansons canadiennes."

Marius Barbeau, En roulant ma boule, 1982, Deuxième partie du Répertoire de la chanson folklorique française au Canada, pp. 571-574. (And earlier publications)

Fowke & Johnston- ""Alouette!" is undoubtedly the most popular and the most widely sung of all our songs. Many people think it originated in Canada, but it was actually imported from France several centuries ago."

E. F. Fowke and Richard Johnston, 1954. Folk Songs of Canada, Waterloo Music Company Ltd., Canada.