A broadside is a single-sheet printed document, usually eighteen to twenty inches high by fifteen or sixteen inches wide, that was suitable for posting on walls or carried, rolled up, to distant places.

The subject matter of broadsides is diverse, ranging from governmental communications and political election notices to poems, memorials, odes and addresses, and even commercial advertisements. The collection contains materials ranging from the American Revolution to gubernatorial proclamations of the present day. The collection of 150 broadsides includes a series of Thanksgiving and Fast Day Proclamations roughly dating from 1763 to 1929. The library has digitized approximately 100 of these broadsides, and has grouped them by general time period.