First off i want to say I have nothing to do with the YouTube channel I will be mentioning in this thread, so I'm not on the make or anything Anyway, I recently came across a channel on youtube called "CivilizationEx". They do very good, very short videos that collate the history and lore of Star Trek, LOTR and ASOIAF, among others. The videos are very good (the narrators voice is especially epic) and if you are looking for a potted history on certain subjects then these are a great place to start. I'll include links to a few of my favs below but one thing to note is that they are not editorial in nature, nobody proposes theories or anything. The videos are just straight collations of all available text on a specific subject and as such have really helped me in developing new theories.
I promise you will enjoy all of these vids and they will definitely get your mind going about something. In particular, the long night vid is really interesting.