Puerto Rico is a commonwealth of the United States located in the Caribbean, east of the Dominican Republic.
Although many players from Puerto Rico have played in the U.S. major leagues, there were also many in the early days who stayed in Puerto Rico. One legendary Puerto Rican player was Pedro Cepeda, the father of Orlando Cepeda. The Puerto Rican League is one of the longest established winter leagues in operation.
Travel went the other way, too, with some famous U.S. players spending some time in Puerto Rico. Josh Gibson is one example.
Puerto Rican players, once plentiful in the major leagues, became less common after it was ruled in the early 1990s that they were not amateur free agents, like their brethren from the Dominican Republic or Venezuela, but had to go through the amateur draft. Having to compete for draft slots against players formed in U.S. high school and colleges was more complicated for young Puerto Ricans, who used to come up through a more informal amateur baseball system. Major League Baseball addressed the problem a couple of decades later with the creation of the Puerto Rican Baseball Academy, established to prepare young players for the amateur draft or to compete for scholarships in U.S. colleges. Signs of the renewal of the Puerto Rican game were its reaching the finals of the 2013 World Baseball Classic and Carlos Correa being drafted first overall in the 2012 amateur draft as part of a strong cohort of young talent coming out of the island.
The greatest name in the history of Puerto Rican baseball is Roberto Clemente, who is considered a national hero for contributions that go well beyond the game of baseball.
- Thomas Boswell: "A Country for Old Pitchers", in How Life Imitates the World Series, Penguin Books, New York, NY, 1982, pp. 33-43.
- Alyson Footer: "MLB working to cultivate talent in Puerto Rico", mlb.com, January 14, 2016. 
- Edgardo Rodríguez Juliá: Peloteros, Editorial de la Universidad de Puerto Rico, San Juan, 1996. ISBN 978-0847702923