Puerto Rico officially the Commonwealth of Puerto Rico (Spanish: Estado Libre Asociado de Puerto Rico, lit. "Associated Free State of Puerto Rico"), is an unincorporated United States territory located in the northeastern Caribbean Sea. It is an archipelago that includes the main island of Puerto Rico and a number of smaller islands as Mona, Culebra, and Vieques. The capital and most populous municipality is San Juan. The territory does not observe daylight saving time, and its official languages are Spanish, which is predominant, and English. The island's population is approximately 3.5 million. Puerto Rico's rich history, tropical climate, diverse natural scenery, renowned traditional cuisine, and attractive tax incentives make it a popular destination for travellers from around the world.

Originally populated by the aboriginal Taíno people, the island was claimed in 1493 by Christopher Columbus for the Kingdom of Spain, enduring several invasion attempts by the French, Dutch, and British. During the four centuries of Spanish rule, the island's ethnic, cultural and physical landscapes were transformed, as the island was settled overwhelmingly by Spanish settlers, primarily from the Canary Islands and Andalusia, continuing right up until the end of the 19th century, as a result of which it is overwhelmingly Catholic and markedly Hispanic territory in terms of culture and language. In 1898, following the Spanish–American War, Spain ceded the island to the United States under the terms of the Treaty of Paris.

Puerto Ricans are natural-born citizens of the United States. Puerto Rico does not have a vote in the United States congress, which governs the territory with full jurisdiction under the Puerto Rico Federal Relations Act of 1950. As a U.S. territory, American citizens residing on the island are "disenfranchised at the national level" and may not vote for president and vice president of the United States. However, Congress approved a local constitution, allowing US citizens on the territory to elect a governor.

A 2012 referendum showed a majority (54% of the electorate) disagreed with "the present form of territorial status," with full statehood as the preferred option among those who voted for a change of status. However, 470,000 voters left the second question blank, leading statehood opponents to suggest that the referendum actually revealed only 45% support for statehood.  Following the vote, the Legislative Assembly of Puerto Rico enacted a concurrent resolution to request the president and congress of the United States to end its current status as an unincorporated U.S. territory and begin the process of admission of Puerto Rico to the Union as a state.