Correspondence of the period 1870-1920 comprises approximately two-thirds of the collection. Included is legal correspondence, 1880-1910, deriving from his membership in the law firm of Lawson and Grunewald; and letters, 1901-1920, concerning the Wisconsin Archaeological Society and the State Historical Society from Charles E. Brown, Reuben G. Thwaites, and others.
The collection also contains considerable data on the Winnebago (Ho-Chunk) and Potawatomi Indians; sketches and drawings of Indian mounds; a small amount of biographical material on Thure Kumlien; a draft of Lawson's biography of Charles de Langlade, Bravest of the Brave (Menasha, 1904); and notes gathered by Lawson while he was writing his History of Winnebago County, Wisconsin: Its Cities, Towns, Resources, People (Chicago, 1908). In notebooks and other papers he collected genealogical data on the Lawson, Baird, Cook, Finney, Fleming, Peper, Williams, and Wright families, which he utilized in his Family Genealogy... (Menasha, 1903). Two scrapbooks contain newspaper clippings of some of his speeches and articles on temperance, politics, and education. Other materials are indicated in the contents list.
