Mauritania

These are real dates: Mauritania's founding is recorded in Wikidata, and accepted here only because they agree with the centuries the atlas independently drew it in. No dissolution is recorded, so the closing year below is still the last century the atlas drew — not when it ended. The atlas itself draws the world at 6 moments in time, not continuously. The strip below covers those snapshots — 1945 CE to 2026 CE — which sits inside the fuller span above.