Walter Piston (1894-1976) was a composer and professor of music.  He spent his entire career at Harvard University, where Leonard Bernstein and Leroy Anderson were among his students.  While there, he also wrote famous textbooks on harmony (2 of them), counterpoint, and orchestration, which are still used at universities around the world.  He began his composition studies while an undergraduate at Harvard, after which he traveled to Paris and was among the many American composers to study with Nadia Boulanger.  His works include eight symphonies, many other orchestral works including a number of concertos, and a wealth of chamber music.  His most famous piece is also his only work for the stage, the ballet The Incredible Flutist.

Tunbridge Fair (1950) is based on a real event, the Tunbridge Fair in Vermont, a large agricultural festival which has run almost every September since 1867.  The piece uses the form ABABA.  The A sections feature an angular, syncopated theme depicting the lively activity of the fair.  These contrast with the B sections, which are much more lyrical and flowing, perhaps depicting the fair’s more tender or nostalgic moments.  It is Piston’s only original work for full band.  It was commissioned by the American Bandmaster’s Association at the behest of famous bandleader Edwin Franko Goldman.

The US Marine Band plays Tunbridge Fair:

For more on this piece, see the Wind Repertory Project, Classical Archives (which makes an inexplicable connection between this piece and Holst’s Hammersmith), Boosey & Hawkes, and this book (Google Books preview).  Also take a look at this analysis of the piece.

Walter Piston has profiles on Wikipedia, The Cambridge Room, PBS, and the American Symphony Orchestra.