Irvin Flores was a political activist, member of the Puerto Rican Nationalist Party and an advocate of Puerto Rican independence. Flores was a leader of the Nationalist faction of Mayagüez, Puerto Rico during the Puerto Rican Nationalist Party revolts of the 1950s. On March 1, 1954, Flores together with fellow Nationalists Lolita Lebrón, Andrés Figueroa Cordero, and Rafael Cancel Miranda entered the United States Capitol building armed with automatic pistols and fired 30 shots. Five Congressmen were wounded, however all the representatives survived and Flores, along with the other three members of his group were immediately arrested.

The Nationalist Party of Puerto Rico is a Puerto Rican political party founded on September 17, 1922, in San Juan, Puerto Rico. Its primary goal is to work for Puerto Rico's independence. The Party's selection in 1930 of Pedro Albizu Campos as its president brought a radical change to the organization and its tactics.