Final answer:
The 20th century was marked by musical modernism, which included atonal and twelve-tone compositions, nationalistic music, and the development of jazz and blues, reflecting the changing cultural landscape and the quest for new musical expressions.
Step-by-step explanation:
The 20th-century music landscape was a rich tapestry of musical evolution and modernism, where composers sought to break free from the constraints of past forms and styles. They experimented with a variety of elements, such as atonal, pantonal, and twelve-tone techniques, strides away from the tonal harmonies and well-structured forms that characterized the music of previous eras. The period saw the emergence of styles with nationalistic fervor and a push towards the boundaries of post-Romanticism and Impressionism.
The distinctive qualities of music in this era include a variety of musical expressions, ranging from the symphony to opera, and the evolution of new forms like jazz, which originated from African American communities and came to feature improvised solos and bolder rhythms. Composers like Mahler and Strauss stretched Romantic capabilities to their limits, while others infused their work with the tone of their own countries, giving rise to strong nationalistic music.
These explorations in the world of music were not just confined to the classical genre. The cultural upsurge of the Harlem Renaissance, for example, introduced blues and jazz, which became international genres. Jazz, with its up-tempo beat and improvised solos, brought in a revolutionary musical style that reflected the life experiences of the African American community.