1. On October 6, 2010, the New Hampshire Supreme Court ruled that the state's same-sex marriage law was constitutional. This made New Hampshire the sixth state to legalize same-sex marriage.

2. On October 6, 1789, the first United States Congress adjourned after their first session, which took place in New York City. This event marked the beginning of the country's legislative process under the new United States Constitution.

3. On October 6, 1866, the state of New Hampshire became the first state to ratify the 14th Amendment to the United States Constitution, which granted citizenship and equal protection under the law to all people born or naturalized in the United States.

4. On October 6, 1961, the El Dorado School in Concord, New Hampshire was the site of the first mass immunization against polio in the state. The vaccine was administered to over 1,000 students, faculty, and staff in an effort to combat the devastating disease.

5. On October 6, 1928, the construction of the Mount Washington Hotel in Bretton Woods, New Hampshire was completed. The hotel was built as a grand resort for affluent travelers, and has since hosted several international conferences, including the 1944 Bretton Woods Conference, which established the modern-day international monetary system.