1. In 1839, the first anti-slavery convention in the United States was held in New York City on September 6. The convention was organized by the American Anti-Slavery Society and was attended by over 200 delegates from various states.

2. On September 6, 1901, President William McKinley was shot while attending the Pan-American Exposition in Buffalo, New York. He succumbed to his injuries eight days later, and Vice President Theodore Roosevelt became the 26th President of the United States.

3. The first Macy's Thanksgiving Day Parade was held on September 6, 1924. Originally called the "Macy's Christmas Parade," it was created to promote the opening of the department store's new flagship location in Herald Square.

4. On September 6, 1952, the United States and Canada signed the Mutual Defense Assistance Agreement, which provided each country with military aid in case of an attack by a foreign power. The agreement marked the beginning of the United States' involvement in the North Atlantic Treaty Organization (NATO).

5. In 1995, the New York Stock Exchange (NYSE) reopened for trading on September 6 after being closed for four days due to Hurricane Gloria. The storm caused significant damage to the NYSE building and the surrounding area, but the exchange was able to resume operations after making repairs.