What's the diffrence between an Empire and a Kingdom, Emperor/King and Empress/Queen?

Question

Just wanted to know!

Answer 1

Traditionally, an empire ranks above a kingdom and therefore an emperor would traditionally rank above a king. Empires, usually, contained a number of states and/or ethnic groups and were usually expansive in size. In fact, an empire almost always had to extend across cultural and ethnic borders to be considered such. Sometimes, an empire would contain kingdoms, such as in the German Empire which contained the kingdoms of Bavaria, Prussia, Saxony and Württemberg.

Some empires, such as the Holy Roman Empire, did not quite include kingdoms but instead were composed of many duchies, margraviates, principalities, etc.

An emperor was usually the sovereign of other sovereigns or the sovereign many collective regions (such as when the Tsar of Russia assumed the title of "Emperor of all the Russias" in reference to his many other Russian royal titles). A king, on the other hand, would oversee his kingdom and his nobility which had little to no sovereign rights.

An example though of an empire without an emperor was the British Empire, headed by the King of the United Kingdom who separately held the title of Emperor of India (but not Emperor of the British Empire).