Otto Emanuel Olsson (19 December 1879 – 1 September 1964) was a Swedish organist and classical music composer.
He studied organ with August Lagergren (1848−1908) and composition with Joseph Dente (1838−1905), both teachers having been employed at the Royal Swedish Academy of Music.
[2] Olsson used his strong background in counterpoint, combined with an affinity for French organ music, to develop his late Romantic style of composition.
He also had an interest in early music and, though not a Catholic but a Lutheran, used the plainchant techniques of Gregorian chant in his Gregorianska melodier.
His activities included serving as a member of official committees that supervised the liturgy and hymnology.