Ceded by Spain in 1898; citizens since 1917; commonwealth since 1952 — status still unresolved.
US commonwealth to the present.
The atlas holds 2 border frames for Puerto Rico (US) — the shape you scrub through changes in 1898 · 1952.
A recent national history covering the 1898 cession, citizenship, and commonwealth status.
On US colonial rule and the nationalist movement in 20th-century Puerto Rico.