In 1916, “Porto” Rico — apparently not yet spelled as “Puerto Rico” — began its current political status, in which its residents are U.S. citizens but Puerto Rico is not itself a state. If it were, Puerto Rico would rank as the 30th-largest state by population, between Connecticut and Iowa.
Its complicated relationship with the U.S. government continues to this day, as I wrote about in my 2015 article for HuffPost Politics: Could The Federal Government Remove The Governor Of Puerto Rico?
Porto Ricans to Have a New Constitution: Organic Act Pending in Senate Will Make Islanders Citizens of United States and Give Them larger Measure of Home Rule
From December 24, 1916