The 369th Infantry Regiment, originally formed as the 15th New York National Guard Regiment before it was re-organized as the 369th upon its federalization, and commonly referred to as the Harlem Hellfighters, was an infantry regiment of the New York Army National Guard during World War I and World War II. The regiment mainly consisted of African Americans. With the 370th Infantry Regiment, it was known for being one of the first African-American regiments to serve with the American Expeditionary Forces during World War I.

The regiment was named the Black Rattlers after arriving in France by its commander Colonel William Hayward. The nickname Men of Bronze (French: Hommes de Bronze) was given to the regiment by the French after they had witnessed the gallantry of the Americans fighting in the trenches. Legend has it that they were called the Hellfighters (German: Höllenkämpfer) by the German enemy, although there is no documentation of this and the moniker may have been a creation of the American press. During World War I, the 369th spent 191 days in front line trenches, more than any other American unit. They also suffered the most losses of any American regiment, with 1,500 casualties. The regiment was also the first of the Allied forces to cross the Rhine into Germany. The lineage of the 369th Infantry is perpetuated today by the 42nd Infantry Division Sustainment Brigade.

On 5 October 1917, Emmett Jay Scott, long-time secretary to Booker T. Washington, was appointed Special Assistant to Newton D. Baker, the Secretary of War. Scott was to serve as a confidential advisor in situations that involved the well-being of ten million African Americans and their roles in the war. While many African Americans who served in the Great War believed racial discrimination would dissipate once they returned home, that did not happen.

Although many African Americans were eager to fight in the war, they were often turned away from military service. When the United States realized that it did not have close to enough soldiers, it decided to pass the Selective Service Act of 1917 which required all men from the ages of 21 to 30 to register for the draft; this included African Americans. Many African Americans enlisted believing that their military service would give them the opportunity to change the way they were perceived by white Americans.

The 369th Regiment was reformed from the National Guard's 15th Regiment in New York. The 15th New York National Guard was a state militia regiment which served to help suppress the 1863 New York City draft riots and was mustered into federal service for 30 days in June 1864, providing manpower for Army posts in the New York Harbor. The 15th Regiment was reconstituted after Charles S. Whitman was elected Governor of New York. He enforced the legislation that was passed due to the efforts of the 10th Cavalry in Mexico, which had passed as a law that had not manifested until June 2, 1913.^{[page needed]}

When the U.S. entered World War I, many African Americans believed that entering the armed forces would help eliminate racial discrimination throughout the United States. Many felt it was "a God-sent blessing" so they could prove they deserved respect from white Americans through service in the armed forces. On the other hand, many were forced through false promises of freedom and equality. Through the efforts of the Central Committee of Negro College Men and President Wilson, a special training camp to train black officers for the proposed black regiments was established.

The 369th Infantry Regiment was constituted on 2 June 1913 in the New York Army National Guard as the 15th New York Infantry Regiment. The 369th Infantry was organized on 29 June 1916 at New York City.

The infantry was called into Federal service on 25 July 1917 at Camp Whitman, New York. While at Camp Whitman, the 369th Infantry learned basic military practices. After their training at Camp Whitman, the 369th was called into active duty in New York. While in New York, the 369th's three battalions were spread throughout New York where they guarded rail lines, construction sites, and other camps.