The bulk of the collection contains correspondence and reports concerning Reed's work of the American Home Missionary Society of the Congregational Church in the 1845-1869. Among the topics addressed are slavery and how the church should regard congregations in slave-holding states, founding of churches in Iowa, church finances, and founding a college in Iowa. This is a rich collection for the study of early Congregationalism in Iowa.

The collection contains “historical manuscripts, notes and correspondence of Professor L.F. Parker in regard to material for his History of Poweshiek County.  Most materials are handwritten, although a few of Parker’s manuscripts are typed.