1. On May 15, 1776, the Fourth Provincial Congress of New Hampshire adopted a new state constitution, becoming the first of the 13 colonies to establish a permanent government separate from British rule.

2. On May 15, 1854, the city of Manchester was incorporated in New Hampshire. It became a major center for textiles and manufacturing in the late 19th century.

3. On May 15, 1885, the trial of Sarah (Jennie) Barnes for the murder of her husband began in Dover, New Hampshire. Barnes was eventually found guilty and became the first woman in New Hampshire to be hanged for murder.

4. On May 15, 1926, Governor John G. Winant signed a bill that established the New Hampshire Fish and Game Department. The department is responsible for managing the state's wildlife resources and promoting hunting, fishing, and outdoor recreation.

5. On May 15, 1936, the Mount Washington Cog Railway opened for its 87th season in New Hampshire. The railway is the world's first mountain-climbing cog railway and has been in operation since 1869.