The Introit Gaudeamus omnes, scripted in square notation in the 14th–15th century Graduale Aboense, honors Henry, patron saint of Finland.
The Introit Gaudeamus omnes, scripted in square notation in the 14th–15th century Graduale Aboense, honors Henry, patron saint of Finland.
Credit: Turku

Gregorian chant is the central tradition of Western plainchant, a form of monophonic, unaccompanied sacred song of the Roman Catholic Church.