Final answer:
The five European nations that lost American colonies by 1821 were Great Britain, France, Spain, Portugal, and the Netherlands. These losses signified a major retreat from European imperialism in the Americas.
Step-by-step explanation:
By 1821, several European nations had lost their American colonies. The five nations that lost American colonies by that time are:
- Great Britain: After a series of conflicts, including the American Revolutionary War, Britain recognized the independence of the United States with the Treaty of Paris in 1783.
- France: France lost most of its North American territories to Great Britain and Spain following the Seven Years' War, as formalized in the Treaty of Paris in 1763.
- Spain: Spain ceded Florida to the British as a result of the same treaty, and by 1821 had lost its colony of Mexico after the Mexican War of Independence.
- Portugal: Portugal's largest American territory, Brazil, declared independence in 1822, following a peaceful path compared to other colonies.
- The Netherlands: Though mainly involved in commerce, the Dutch lost influence in many of their territories as a result of various European conflicts and shifting powers.
These losses marked a significant retreat from European imperialism in the Americas and ushered in a new era of independence for former colonies.