Born in England, Hewitt arrived in New York in 1792 and from his arrival to 1808, he conducted the orchestra of the Park Street Theatre and arranged and composed music for the theatre as well.
From 1811 until 1816, Hewitt and his family moved to Boston and Hewitt conducted the Federal Street Theatre. Though he returned to New York in 1816, he began to tour heavily until an operation in 1826 that was unsuccessful and lead to his death in 1827.
Of particular note is Hewitt's devotion to publishing music and throughout his life published over 639 compositions, including those of British composers and at least 160 of his own. His own compositions are largely based on American patriotic tunes and ballads, essential publications in establishing a unique American musical language.
Source: New Grove Dictionary of Music and Musicians