In 1867, the State Cabinet, an extensive collection of specimens representing the natural history of Massachusetts, was transferred from the State House in Boston, MA, to the new Massachusetts Agricultural College in Amherst (now the University of Massachusetts). The botanical portion of the State Cabinet has remained intact, and relatively unknown, for the last 148 years at the University of Massachusetts Herbarium. Over the course of two years we completely curated the collection, performed restoration work, and researched the history of the collectors associated with the State Cabinet with a goal of making the collection available online. We were able to assign collectors and collection dates to 84% of the collections that were missing this information. The primary collectors, Charles Jarvis (1800–1826), Edward Jarvis (1803–1884), and Henry Little (1802–1826), were a group of Harvard-educated physicians whose botanical interests were probably inspired by the instruction they received in natural history at Harvard University. The State Cabinet consists of 1509 sheets and includes 905 taxa, an increase from the original, sometimes incomplete identifications based on the Linnaean System. Most of the plants in the collection are from the greater Boston, MA, area, particularly Concord, MA. The Jarvis collection includes the earliest recorded specimens from Concord, MA, and the Little collection includes a few early specimens from the White Mountains as well as specimens cited in the second edition of Bigelow’s Florula Bostoniensis published in 1824. The State Cabinet provides a window into early 19th century botany in New England.