...either way, the representation of noble titles and English history present is spotty at best.

A noble court's rankings, from greatest to least, follow like so:

Monarch, Prince, Archduke, Duke, Viceroy, Marquis, Earl and Baron. 

These are the inherited titles, and each corrosponds to the land that the noble rules over; a duke rules a duchy, a baron rules a barony, and so on. Knights, followed by squires, are non-inherited titles, and generally don't come with lordship over a region. "Lord" is a generic term of address, not a rank.

Specifics vary by culture, language and time period, but that's generally how it goes.