Oscar O'Brien (07/09/1892 - 20/09/1958), a Canadian folklorist, composer, pianist, organist, teacher, born in Ottawa. He studied piano and organ with Amédée Tremblay while pursuing his studies at the De La Salle Academy and the University of Ottawa, and at the age of 16 was appointed Tremblay's deputy organist at the Notre-Dame Basilica. In 1915 he began a 15-year collaboration with Charles Marchand as the latter's accompanist and arranger. Two years later he moved to Montreal as a teacher, orchestral pianist, and accompanist. Because of Marchand's influence folk music remained central to O'Brien's activities. Their collaboration intensified through tours, recordings, and recitals, and in 1927 they performed in Quebec in the first CPR Festival, O'Brien participating as composer, arranger, and pianist. They also took part in the 1928 Festival. With Marchand's untimely death before the 1930 festival O'Brien became the assistant music director of the festival, the last one held in Quebec. During the ensuing 15 years (1930-45) O'Brien served as the artistic director of the Alouette Vocal Quartet and wrote many of the group's arrangements. He entered the Benedictine monastery of St-Benoît-du-Lac, Que, in 1945 and took his vows in 1947. He was ordained a priest in 1952, and from then on was known as Dom Oscar O'Brien.