In October 1771, he arrived in Philadelphia via Rotterdam and became an indentured servant to goldsmith William Taylor for one-and-a-half years.
Although Aitken was buried in an Episcopal cemetery, he took an active part in Philadelphia's Catholic community as a member of Old St. Mary's in the 1780s and 1790s—he served as godparents to several of the parish's children, regularly donated to the church, and rented a pew there.
[6] Although there is scholarly debate as to whether the work, which spans 136 pages, is representative of actual Catholic musical practice in post-revolutionary America, Reverend John Carroll approved its publication—his signature, along with those of three Philadelphian priests, appears in an approbation preceding the title page, which endorsed "an undertaking so conducive to the Decency and Solemnity of Religious Worship".
[3] Between 1793 and 1806, he only published two works: a collection entitled Scots Musical Museum (1797) and "The Goldsmith's Rant" (1802).
[9] In 1807, Aitken returned to regularly publishing music, opening a shop on North Second Street.