The Mary Callum Wiley Papers date from 1847 to 1966 and contain correspondence, diaries, essays, greeting cards, manuscripts, newspaper and magazine articles, photographs, printed items, scrapbooks, speeches, and other miscellaneous items.

Mary Callum Wiley was a prolific writer. In addition to the many newspaper articles, she wrote poetry, essays, and magazine articles. She also wrote several books including The Teacher's Manual, Hill's Young People's History of North Carolina and a children's book entitled Ann Dorothea Her Book which was not accepted for publication by Little, Brown & Company in 1936. Her diary dating from 1894 to 1906 deals mainly with her teaching days in Salisbury, North Carolina. At the end of the diary are lists of books she read, favorite songs, authors, flowers, essays, people with whom she corresponded, and money received and spent during that period. Also contained in the collection are published copies of her newspaper article "Mostly Local" written between 1947 and 1957, as well as photocopies of typewritten galleys of "Mostly Local" articles.

The collection contains the correspondence of family members. The letters written by business acquaintances to Reverend Calvin H. Wiley between 1847 and 1866 indicate he communicated with people all over North Carolina and as far away as Boston, Massachusetts. Annie W. Wiley's correspondence covers the period 1897 to 1924. Mainly it consists of personal letters between her and her mother while she taught at the State Normal School. There are also letters between her and her two sisters, Mary Callum Wiley and Mittie T. Wiley. Mrs. Calvin H. Wiley's correspondence dating from 1857 to 1916, is mainly personal letters between her and her mother, her sister, her daughters, and her friends. Mittie T. Wiley's 1891 to 1966 correspondence consists of personal letters between her and her family, and her friends. Mittie T. Wiley's scrapbook, dating from 1901 to 1904, includes drawings, fabric samples, and writings.