Romantic music
In the early part of the 20th century, many composers wrote music which was an extension of 19th-century Romantic music, and traditional instrumental groupings such as the orchestra and string quartet remained the most typical. Traditional forms such as the symphony and concerto remained in use. Gustav Mahler and Jean Sibelius are examples of composers who took the traditional symphonic forms and reworked them. (See Romantic music.) Some writers hold that Schoenberg's work is squarely within the late-Romantic tradition of Wagner and Brahms and, more generally, that "the composer who most directly and completely connects late Wagner and the 20th century is Arnold Schoenberg".