Main Hall was named to honor President John Hanson Thomas Main, who conceived of and carried forward the idea of Grinnell as a residential college. Through the investment of about $1 million, the College built the Women's Quadrangle in 1915, and the men's halls in 1916-17.

Main Hall serves as the central building of the South Campus residence Halls, and at the time of its opening, it included a beautiful drawing room, an inspiring Gothic dining room, and the Little Theatre. Gardner Lounge, in the basement of Main Hall, has hosted performances by Smashing Pumpkins, Nirvana, and more.