Chronas is a history project linking Wikipedia and Wikidata with a chronological and cartographical view. Travel back in time and watch realms being founded, grow and disappear again.
On the interactive map you can adjust the time slider at the bottom of the page to see national boundaries change through the course of history. Stop the time slider at any point and click on the map to reveal a Wikipedia entry about that nation. You can set a starting year and use markers for military, explorers, politicians, religious, scientists, cities, castles, battles and more.