The members of Beloit College's class of 1866 first formally organized their Class Union Society at the Wisconsin college's preparatory school in November 1861. The society's purpose was the "advancement of the class and the better maintainance [sic] of unity." Most of the members were from Wisconsin or Illinois. In 1864, several of the students joined the Union Army for 100-day enlistments.
From the guide to the Beloit College Class Union Society minutes, 1861-1866, (William L. Clements Library, University of Michigan)