The Hulbert collection consists principally of late eighteenth century documents related to colonial British America. The collection also includes documents from the American Revolution and early national period.

Four significant subjects stand out in the collection. The first concerns a dispute among colonial New York officials over their respective rights to collect and receive patent and other fees (1766-1770). This material includes extensive correspondence, petitions and other documents, especially from Goldsbrow Banyar, Register of Prerogative Court and deputy to George Clark, Secretary of the Colony of New York. A second substantive set of papers concerns the Bahamas (1795-1796) and includes correspondence, principally to and from colonial agent George Chalmers, requesting more troops in war with Spain; resolutions of the Colonial House of Assembly; and minutes of the Legislative Council. A third set includes Captain Frederick de Deimar's post-war efforts to be reimbursed by the British government for expenditures related to the troop of Hussars he raised in America during the Revolution; Diemar's collected documents include enlistment and other certifications, correspondence, receipts, and rolls of the soldiers, clothing and equipment. A fourth set includes several monthly military returns (i.e., statistical reports) concerning the British forces in North America during the French and Indian War in 1760.

In addition to these subjects, the collection includes various other British colonial military papers, including naval orders, reports of promotions, Order in Council concerning troops in Newfoundland (1698), and an act punishing those assisting Royal Navy deserters (1760). Other than military matters, the collection includes land grants and indentures, a will, court filings, and other documents from New York State, Rhode Island, South Carolina, Virginia, and West Florida. Several of these legal documents, which primarily concern property matters of various types, including enslaved African-Americans in Virginia, still have a large wax seal tied to them.