https://c1.staticflickr.com/5/4596/24556520177_d5a5b6d97a_o.png

https://www.worldhistory.org/timeline/empire/

https://www.nationalgeographic.org/lesson/european-borders-through-history/

https://www.visualcapitalist.com/mapping-greatest-empires-history/

https://www.knowledgesnacks.com/articles/empires-at-their-greatest-extent/

https://moverdb.com/world-border-age/

https://www.visualcapitalist.com/map-worlds-borders-by-age/

https://moverdb.com/world-border-age/

https://en.wikipedia.org/wiki/List_of_largest_empires

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