History

As one of the oldest and most diversified cultures in the world, Puerto Rico is a vibrant, modern, bilingual, multicultural society, one that has been molded by Spanish, African, Indian and U.S. influences.

to the right is a picture of history ruins in old san juan

The U.S. House of Representatives, and the Jones Act of 1917, established all Puerto Ricans are born citizens of the United States with the identical citizenship of any US Citizen. You do not need a passport to visit Puerto Rico from anywhere in the 50 states.
http://www.gotopuertorico.com/puerto-rico-vacations.php
Residency of Puerto Rico, however, is a little different than amongst the 50 states.. No residents of Puerto Rico pay federal income tax ( unless you are a Federal Employee or derive income from the US mainland some people pay both federal and local tax but are not taxed twice on any income) nor vote in presidential elections, but pay most other federal taxes, including Social Security, Medicare, Medicaid, etc., and many commerce-related taxes like the alcohol tariffs. When any resident of Puerto Rico moves and changes residency to one of the 50 states, then they must commence paying federal income tax and can vote in presidential elections . .
Our currency is the U.S.dollar, our mail system is the U.S. Mail, we have Federal Courts, the U.S. Coast Guard, the U.S. National and Air Guards, and even the F.B.I.
Puerto Ricans have spilled their blood in every war and conflict in which this nation has entered since World War One. Five Puerto Ricans have received the Congressional Medal of Honor posthumously. Over 50 Puerto Ricans have already died in Iraq and Afghanistan defending US policy. Two Puerto Ricans have served as Surgeon General of the United States. Numerous Puerto Ricans hold decisive positions in government’s agencies, like NASA.
Puerto Rico could be said to be a separate 'cultural nation', but politically it is part of the United States. Puerto Rico is a Commonwealth of the US, some say territory . . . some say it is more like a state. As far as the local Puerto Rican vote, only 4 to 5% ever vote for the independence ticket, the rest is divided between remaining a commonwealth or becoming an official state.


http://www.elyunque.com/history.html