The microfilm is arranged in three series:

I. Correspondence and Reports

II. Administrative Records

III. Youth's Penny Gazette and Catalogs

The Youth's Penny Gazette was one of many ASSU periodical publications; it was perhaps the most successful of these, and is the only one included in the microfilm edition of the ASSU papers.

The major bulk of the microfilm edition is devoted to Correspondence and Reports--the incoming letters, etc., from over two thousand missionaries. For some of these men only a few letters exist, while others' work is reflected by a lengthy list of letters. Some of the more substantive sets of correspondence are mentioned here. William Blair was the first trained missionary, hired in 1821. His first year witnessed two thousand five hundred miles of travel and the founding of sixty-one Sunday schools; he was so successful that the concept of the paid full-time missionary caught on. By 1824, Timothy Alden and M. A. Remley were actively employed. The first decade of this venture saw especially energetic work from Joseph Bruce Adams, working from New York to Mississippi especially among the Chicksaw and Choctaw Indians; Gottlieb Shober, who served among North Carolina Moravians; Alvah Sanford in Vermont; and Randolph Stone and E. Judson in Ohio. In 1830, the ASSU began its Mississippi Valley Enterprise, the initial success of which was largely due to James Welch's untiring efforts in the field.

The correspondence reflects social and political history as well. Cholera and other epidemics are traceable. As the mid-nineteenth century approached, slavery became a topic of discussion; see particularly letters of W.C. Dunlop, A. Hay. and Alfred Taylor. The Civil War is documented by civilian missionaries Thomas Campbell and W.S. Sedwick, and also by soldier missionaries John McCullagh and Henry Clay Trumbull; J.B. Marsh's letters describe Reconstruction policies' effects.

Post-war work saw the missionary force of the ASSU double by the turn of the century. Especially significant letters are those of William Paxton in Missiouri; Martin B. Lewis in Wisconsin and Minnesota; Charles Frady, working with Indians in the West; and Thomas Lain, ministering to Blacks and Indians in Texas and Oklahoma.

The ASSU sponsored some missionaries to foreign countries as well. Several were in Canada; Chester Holcombe was in China in 1869 as was S. Wells Williams in 1842. Robert Baird wrote from France in 1835 and 1840, and from Germany and Russia in 1840. S. B. Munges ws in Bombay, India, in 1835; W. Ramsey wrote from that city in 1831-33. J. C. Fletcher sailed along the eastern coast of South America in 1862, stopping at Rio de Janerio and other ports.

Description of the arrangement of the collection, with reel list, and index of ASSU missionaries and geographic locations, can be found in the Sokolosky American Sunday School Union Papers 1817-1915: Guide to the Microfilm Edition, in the Archives Reading Room.