Imperialism is a form of government where a stronger nation or state exerts control over a weaker nation or state. The most common form of imperialism is colonial imperialism, where a stronger nation or state takes control of a weaker nation or state by establishing political, economic, and sometimes military control. Imperialism has existed since antiquity, with the Romans, Greeks, and Egyptian empires having been some of the most famous. In the modern era, European nations such as France, Britain, and Spain had major imperialistic endeavors around the world, forming vast overseas empires that included parts of Africa, Asia, and Latin America. During the 19th and 20th centuries, Japan and the United States also had imperialistic ambitions as they sought to expand their economic and military influence in other countries or regions. Imperialism has had a huge impact on global history, from creating cultural and economic exchanges between different societies to sowing divisions and creating conflict. Despite the fact that the formal age of imperialism has largely come to an end, its effects are still felt around the world today.