1. 1776 - The Museum of the American Revolution Opens: The Museum of the American Revolution opened its doors to the public on March 9, 1776 in New York City. The museum aimed to provide a visual and interactive experience of the American Revolution, showcasing key figures and events that helped shape American history.

2. 1914 - The First Subway Line Is Completed: On March 9, 1914, the first subway line in New York City was completed. The line connected City Hall with 145th Street. It was a major transportation breakthrough as it reduced travel time and facilitated the movement of people around the city.

3. 1933 - Governor Al Smith Announces Plan To Create New York State Park System: Governor Al Smith announced the creation of the New York State Park System on March 9, 1933. His vision was to preserve and protect natural areas within the state for public use and enjoyment. Today, the New York State Park System covers over 330,000 acres, with over 200 state parks and historic sites.

4. 1959 - The Barbie Doll Is Introduced: On March 9, 1959, the Barbie Doll was introduced by the toy company Mattel. The doll quickly became an icon in American culture, influencing fashion and popular culture for decades to come. Barbie has also been the subject of controversy throughout the years regarding the doll's body image and impact on young girls.

5. 1989 - The Death of Robert F. Wagner, Jr.: On March 9, 1989, Robert F. Wagner, Jr. passed away at the age of 80. Wagner was a prominent political figure in New York, serving as the mayor of New York City from 1954 to 1965. He was known for his progressive policies and initiatives, including the creation of the New York City Housing Authority and the establishment of the first municipal health insurance program.