The true march music era existed from 1855 to the 1940s when it was overshadowed by jazz, which the march form influenced (especially in ragtime). American march music cannot be discussed without mentioning "The March King", John Philip Sousa, who revolutionized the march during the late 19th and early 20th centuries. Some of his most famous marches are "Semper Fidelis", "The Washington Post", "The Liberty Bell", and "The Stars and Stripes Forever". Sousa's marches are typically marked by a "subdued" trio, as in "The Stars and Stripes Forever" in which the rest of the band becomes subordinated to arguably the most famous piccolo solo in all of music. Typically, an American march consists of a key change, quite often happening in coordination with the Trio. The key may change back before the song is over, especially if the Trio ends well before the last few bars of the march.