Louis XIV was called the Sun King because, like the galaxy revolving around the sun, France revolved around Louis.

Ivan the Terrible was the final Duke of Moscow and the first Czar of Russia. He declared himself to be the emperor of Russia when his Duchy of Moscow grew so large that it reached the size and stature of an empire, thus needing a new name.

The nobility of Russia were referred to as Boyars, which is derived from old Turkic meaning rich men. Members of the peasant class were referred to as "kulaks."

The estates General functioned similarly to, but was functionally much weaker than, the English Parliament. It was their job to raise taxes, recruit soldiers, and enforce laws in the provinces. Louis appointed trusted people to do these tasks, and thus never called the Estates General to session.

Conservative ideology developed as a response to the political upheaval of the French Revolution. This is best demonstrated in the ideas of Edmund Burke. Liberals took the defense of individual liberties as one of the cornerstones of their ideology. The abolition of slavery took place after Conservative ideology began developing. Socialists, rather than Conservatives, responded most directly to the social changes caused by the Industrial Revolution. 

Ivan V was Peter's elder half brother, and therefore was also the rightful heir; however, Ivan was severely hindered by physical and mental disabilities and was unfit to rule. Therefore he and his younger brother Peter were named co-Czars so Ivan could rule in name and Peter in practice until the time of Ivan's death.

Henryk Walezy was the first man elected to be King of the Commonwealth. He was actually a son of the reigning King of France, and he abdicated the throne in order to become King of France in 1574.

Henry Valois was the third son of the French king, leaving him with the opportunity to accept the throne of the Commonwealth when offered. However, both his older brothers died young, and had no heirs, thus leaving the throne of France to Henry who quickly abdicated from rule of the Commonwealth in order to return to France and become king.

The Sejm is the Polish Parliament. Historically members were elected by popular vote of landed nobility. Today it is elected by universal ballot.

Frederick I declared himself King in Prussia because Prussia was still an Elector of the Holy Roman Empire, and thus he had to pledge loyalty to the Holy Roman Emperor. As such he could not declare himself King of Prussia, as that would mean he claimed all sovereignty over Prussia, and that would cause conflict with the Emperor; however, the Emperor allowed Frederick to give himself the title of King in Prussia, so he could still be a king, but still pledge Prussia to the Emperor.