Can some body tell me what this means, please?

Question

Kings and Queens rule countries or (more traditionally) kingdoms. Emperors and emperesses rule empires. Empires are made up of many smaller units that either are partially independent or were independent at one time.

Answer 1

An empire might be a bunch of monarchies that are seized or decide to unite under a single ruler.

Or, an empire may seize land that's only part of a monarchy or other empire.

Like, say, the Roman Empire.  It held most of Europe at one time, and most of those places had been monarchies before they were conquered.  An empire could also take over stuff from another empire.

And it's empress, not emperess.

In the Roman empire, parts were usually ruled by people further down the chain of command.  Like, say, a local governor, that sorta thing.

Kingdoms are generally hereditary and used to be  smaller than countries (though, through marriage or conquest, most kingdoms wound up country-sized.)  Empires are sometimes hereditary after the initial emperor, but are usually started by some guy like Alexander the Great going around seizing stuff.  Bear in mind that sometimes "seizing" isn't particularly violent or acrimonious--sometimes small areas feel they'd do better under an empire than on their own.

I mean, not lately.

Like the n**i empire.  That didn't go so well for anybody.  Nobody liked being seized by the n***s.

But the Roman empire had its pros and cons.  

And empires always fall, though "kingdoms" or countries tend to stay together over time.