1. On March 31, 1640, the town of Dover, New Hampshire was founded. It was the first permanent settlement in New Hampshire and one of the oldest in the United States.

2. On March 31, 1776, Abigail Adams wrote a letter to her husband John Adams, who was attending the Continental Congress in Philadelphia. In the letter, she famously urged him to "remember the ladies" when drafting the new laws for the newly formed United States.

3. On March 31, 1805, Meriwether Lewis and William Clark began their journey to explore the Louisiana Purchase territory. They had been commissioned by President Thomas Jefferson to explore the western part of the continent and find a water route to the Pacific Ocean.

4. On March 31, 1854, the New Hampshire legislature passed the first statewide prohibition law in the United States. The law prohibited the manufacture and sale of alcohol, although it was largely ignored and ultimately repealed in 1878.

5. On March 31, 1936, the Old Man of the Mountain, a famous natural rock formation in Franconia Notch State Park, was officially designated as the state emblem of New Hampshire. The Old Man of the Mountain was a beloved symbol of the state for many years, but sadly collapsed in 2003.