1. In 1886, May 1 became an important date in New York labor history when tens of thousands of workers went on strike to demand an eight-hour workday. This strike, known as the Haymarket Riot, resulted in the deaths of several workers and the imprisonment of many others.

2. May 1 is also significant in New York immigration history. Ellis Island, which opened on May 1, 1892, became the primary entry point for immigrants coming to the United States through New York until 1954. Over 12 million immigrants passed through Ellis Island during its operation.

3. On May 1, 1917, the first quota system for restricting immigration was enacted in the United States. The Immigration Act of 1917 set a limit of 3 percent of each nationality's population already living in the U.S. in 1910, effectively restricting immigration from southern and eastern European countries.

4. May 1, 1926 saw the opening of the famous Waldorf Astoria Hotel in Midtown Manhattan. The hotel was the largest and tallest hotel in the world at the time and hosted numerous famous guests including Winston Churchill, Marilyn Monroe, and Franklin D. Roosevelt.

5. In recent years, May 1 has become known as May Day, a day for workers' rights protests and demonstrations in New York and other cities around the world. In 2000, thousands of protesters took to the streets of New York City to rally against police brutality and globalization in a demonstration known as the "May Day 2000" protest.