There was a unit bearing that name in Newbury Port, Massachusetts, during the 1840s. Two music sheet, one uncoloured, the other coloured, dedicated to the "officers and members of the Washington Light Guard of Newbury Port" were printed in Boston in 1848. The music was "Capt. Coffin's Quick Step". The guard's uniform included a bearskin cap, a red coatee with gold buttons and medioum blue trousers, its band having shakos, a dark blue uniform with gold buttons and red belts.
The music sheets that I found of this unit are in the Anne S.K. Brown Military Collection housed in the John Hay Library at Brown University, Providence, RI.
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