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"Chester" is an American hymn tune. It was originally composed by William Billings in 1770 (revised in 1778) as a patriotic anthem for New England. It was frequently sung during the American Revolutionary War, its popularity rivaled only by "Yankee Doodle" as a unofficial national anthem. In 1786, the tune was also used for one setting of Philip Doddridge's hymn Let the high heavens your songs invite, written in England in 1755. This use of the tune became a favorite of Sacred Harp singers in the American South, finding use in Protestant church services.
Sometime during the Human-Covenant War, an Unggoy learned to sing the altered version of the song from a human prisoner who eventually perished in captivity. In 2558, he sang part of the tune to Fireteam Osiris at a Swords of Sanghelios base camp. Spartan Jameson Locke thought it was an interesting song.
Let the high heav'ns your songs invite,
The title of the song reflects a common practice of Billings's day, in which tunes were labeled with (often arbitrarily chosen) place names. The idea behind this practice was that by labeling the tunes independently, one could sing them to different words without creating confusion. Chester is thus the tune of both Billing's anthem and Doddridge's hymn.
List of appearances