The collection consists of private and public papers relating to his involvement in the American Revolution, the Declaration of Independence, the U.S. Constitution, the U.S. presidency and governorship of New Hampshire.

Langdon writes that he is "very unhappy at the behaviour of our Men owing entirely to the Officers, which I've mentioned to our Assembly and Council ... our Assembly will send to all the Towns, to apprehend all those Soldiers who have ...

Both men served in the Continental Congress; Langdon signed the Constitution, Bartlett, the Declaration of Independence.