Julius Engelbert Röntgen (9 May 1855 – 13 September 1932) was a German-Dutch composer of classical music. He was a friend of Liszt, Brahms and Grieg.Julius Röntgen was born in Leipzig, Germany, to a family of musicians. His father, the Dutch born Engelbert Röntgen, was first violinist in the Gewandhaus orchestra in Leipzig; his mother, Pauline Klengel, was a pianist, an aunt of the renowned cellist Julius Klengel, born in 1859.