I've been listening to a great CD called Simple Gifts: Shaker Music in America. It's a terrific collection of 34 traditional Shaker hymns. Here's an excerpt from the album notes:

Shaker song, despite growing interest in the Shaker movement, remains virtually unknown to the general public. Reductionistically, one tune (admittedly, a beautiful one) has come to symbolize all of Shakerdom. Even that tune, Simple Gifts, is most often heard in reworkings, ranging in context and quality from the brilliant (Aaron Copland's Appalachian Spring) to the downright tacky (television commercials for expensive automobiles). And yet, Shaker music is so very much more! The large, mainly unpublished body of Shaker song contains untold treasures; it is important as music, as spiritual testimony, and as American cultural history. The repertoire fairly cries out to be heard on its own terms, in a simple, non-exploitative context.
We can never know exactly how the nineteenth-century Shakers performed their music. Some aspects of their style have surely been lost to later generations. But the musicians of this recording, both Shaker and non-Shaker, have aimed to shape their performances along traditional lines, according to the precepts and the spirit of Shaker practice. Early Shaker song, like medieval Gregorian chant, was to be done in unison, by voices only, without instrumental accompaniment. Shaker melodies of the early period are noticeably "archaic", they can and do sound "older" than their dates of composition would appear to indicate. The influence of English folksong is immediately evident, and there are even reminiscences within the Shaker repertoire of medieval and Renaissance song style. Many songs were composed by, or "given to", specific individuals in the community. Some, like the dance tunes, were sung by small groups of singers during the worship service, as the main body of believers joined in the dance. Others were meant for performance by the whole community. We have attempted to vary the dispositions and groupings of voices across this recorded program without departing from the basic tenets of Shaker performance practice.
The Shakers carefully preserved thousands of their songs in various kinds of special musical notation ("normal" staff notation, along with part-singing and instrumental playing, did not come into general use until after 1870). The library of the Shaker community at Sabbath-day Lake, Maine, contains extensive music holdings, including some important manuscripts by Elder Otis Sawyer, a key figure in the history of Maine Shakerdom and a fine musician. Many of the songs we perform were transcribed during the spring of 1994 from original Shaker manuscript and printed sources; a large number of these from Elder Otis' lovingly preserved copy books. This scribe/editor, who worked on song transcriptions in Maine for a number of happy days as Elder Otis' framed photographic portrait looked down at him from the facing wall, felt privileged to be helping these tunes along on their way to a deserved rebirth. It seemed that the beautiful inspirations of Elder Otis and the early Shakers were preparing to speak to the world once again, and there was a rightness to that.
But the archives do not tell the whole story. Shakerism is also a living religion, with a continuous musical tradition. Although the early Shaker "letteral" notation was abandoned over a century ago, many older Shaker songs have been preserved in communal memory at Sabbathday Lake, and are still being sung by the Shakers of today. My deepest thanks go to the members of the Sabbathday Lake Shaker Community, for warm hospitality, good advice, unstinting project support, and musical inspiration.
Joel Cohen
Newburyport, Ma. Spring 1995

I found a review of the album (see link above) that says that "Simple Gifts," the most famous of all Shaker songs, was penned by Elder Joseph Brackett, 1797-1882.
-Joe Offer-