His father, Ole Peter Johannesen (1816–1890), was from the Borg farm in Solør, from which the family name originated.

When in 1881, conductor Friedrich August Reissiger resigned as director of the 1st Brigades Band, Oscar Borg was his replacement.

[2] Borg's compositions are characterized by good melodies, euphonious harmonies and skillful instrumentation.

He received the King's Medal of Merit in gold and was made a Knight 1st Class of the Order of Vasa.

He was awarded the King Oscar II Medal in gold, and Kaiser Wilhelms Krieg Verdienstmedalje.