The military defense of Puerto Rico is the responsibility of the United States as part of the Treaty of Paris. Locally, Puerto Rico has its own National Guard, the Puerto Rico National Guard, and its own state defense force, the Puerto Rico State Guard, which, by local law, is under the authority of the Puerto Rico National Guard. The commander-in-chief of both forces is the governor of Puerto Rico, currently Pedro Pierluisi, who delegates his authority to the Puerto Rico Adjutant General, currently Major General José J. Reyes. The Adjutant General, in turn, delegates the authority over the State Guard to another officer but retains the authority over the Puerto Rico National Guard as a whole. At the national level, the commander-in-chief is the President of the United States, currently Joe Biden.
John Little McClellan was an American lawyer and segregationist politician. A member of the Democratic Party, he served as a U.S. Representative (1935–1939) and a U.S. Senator (1943–1977) from Arkansas.
Major General Luis Raul Esteves was the first Puerto Rican and the first American citizen of Hispanic heritage to graduate from the United States Military Academy, and the founder of the Puerto Rico National Guard. Of his West Point class, that included Dwight Eisenhower, Omar Bradley, Joseph McNarney, James Van Fleet and George E. Stratemeyer, Esteves was the first to achieve the rank of general.
The recorded military history of Puerto Rico encompasses the period from the 16th century, when Spanish conquistadores battled native Taínos in the rebellion of 1511, to the present employment of Puerto Ricans in the United States Armed Forces in the military campaigns in Afghanistan and Iraq.
Phi Sigma Alpha (ΦΣΑ), commonly known as La Sigma, is a Puerto Rican fraternity originally established as the Sigma Delta Alpha Fraternity on October 22, 1928, at the University of Puerto Rico by twelve students and a professor. Phi Sigma Alpha can trace its roots back to 1898 to the Union Hispano Americana, as well as to the first ever Greek letter Hispanic-oriented fraternity, Sigma Iota, established in 1912. By 1998 there were over 4,376 members.
Lieutenant General John B. Conaway is a retired United States Air Force officer who served as Chief of the National Guard Bureau from 1990 to 1993.
Puerto Ricans and people of Puerto Rican descent have participated as members of the United States Armed Forces in the American Civil War and in every conflict which the United States has been involved since World War I. In World War II, more than 65,000 Puerto Rican service members served in the war effort, including the guarding of U.S. military installations in the Caribbean and combat operations in the European and Pacific theatres.
Dr. Juan Arturo Rivero Quintero was a Puerto Rican biologist who founded the Dr. Juan A. Rivero Zoo at the University of Puerto Rico's Mayagüez Campus.
Emmett H. 'Mickey' Walker was a U.S. Army lieutenant general who served as the Chief of the National Guard Bureau from 1982 to 1986.
Charles Cuprill Oppenheimer was a lawyer, Rotary District Governor for Puerto Rico, a war veteran, and a retired major general in the Puerto Rico National Guard.
Major General Enrique Méndez Jr. Grau, was a United States Army officer who was also the first Puerto Rican to hold the positions of Army Deputy Surgeon General, Commander of the Walter Reed Army Medical Center and Assistant Secretary of Defense for Health Affairs. He was also the Dean and President of the Ponce School of Medicine in Puerto Rico. Also served as Secretary of Health of Puerto Rico.
William Riefkohl López was the executive director of the Puerto Rico Manufacturers Association 2002–2013.
Luis Stefani Raffucci was a long time Chancellor of the University of Puerto Rico at Mayagüez.
Lieutenant General Herbert R. Temple Jr. is a career military officer who served as Chief of the National Guard Bureau.
John Robert D'Araujo Jr. is a retired United States Army major general who served as Director of the Army National Guard and an official with the Federal Emergency Management Agency. He is the first Portuguese American to achieve the rank of major general.
Roger C. Schultz is a retired United States Army lieutenant general who served as director of the Army National Guard.
Richard D. Dean is a retired United States Army brigadier general who served as Deputy Director of the Army National Guard.
Herminio M. Brau del Toro, was a Puerto Rican lawyer, engineer, professor, writer and industrialist.
Zeta Mu Gamma (ΖΜΓ) is a high school Fraternity established in Mayagüez, Puerto Rico on March 12, 1943.
United States Army Reserve 
Army National Guard 
Major general 
