Swedish composer and pianist, born in Germany. He initially received musical instruction from his father, Karl Behrens, a flutist and composer, and later studied under Karl Reissiger in Dresden. He settled in Sweden in 1847, performing in chamber music concerts in Stockholm, and quickly gained renown as a pianist. In 1861, he was appointed lecturer in composition at the Royal College of Music in Stockholm, and in 1868, he became a professor. He also served as piano teacher to Queen Lovisa for a period.