While imperialism in the 19th and 20th centuries largely involved Western European countries imperializing countries and peoples in Asia, Africa and the Americas, there are few if any countries that have not been on the losing side of imperialism at some point or another. While the Age of Imperialism lasted from around 1700 until the middle of the 20th century, imperialism in the broader sense of using military, economic and political strength to gain control over other lands and peoples has existed since the beginning of civilization.
Modern examples of imperialism are numerous. Every nation in the Americas is an example of the imperialism of nations like Spain, England, France and the Netherlands, while many Asian countries like Vietnam and India were once conquered and ruled by European countries. The entirety of Africa, with the exception of Liberia and Ethiopia, was also divided up by European powers during the Scramble for Africa in the 19th and 20th centuries. Even countries that were not directly ruled by outside powers fell under the influence of one or more European powers. For example, although Japan maintained its independence, it was forcibly opened to trade by the United States.
However, imperialism dates back far earlier than modern Europe. The Persian and Assyrian Empires, for example, practiced aggressive military imperialism, while the Romans famously used imperialism to form an empire from Britain to Egypt. Even England, the nation that would eventually go on to form the largest empire ever seen, was once subject to imperialism; after the Battle of Hastings in 1066, the Anglo-Saxon English were subjugated by the Normans. Like their future conquests, they lost their autonomy and, to a degree, even their culture and language to foreign invaders.