Sparta Remix is the name given to a mash-up remix based on a scene from the 2007 movie 300. It is a specific kind of remix that requires perfect timing.
Someone who makes Sparta remixes is stated as a Sparta Remixer (SR). A Sparta base is simply the instrumental base, BGM (background music), or the backing track of a Sparta remix. Someone who makes Sparta bases is stated as a Sparta Base Maker (SBM).
Keaton Monger, the creator of the Sparta Remix, released his 300 This is Sparta (fun times mix) video in 2007. He posted it on YTMND (which stands for "You're The Man Now Dog", a punchline by British actor Sean Connery on one of his non-James-Bond movies), where it gained considerable popularity. But the fad really didn't start until he decided to extend his remix, and the EXTENDED fun times mix was put in several videos containing Sparta GIF's and memes at that time. The tempo of Sparta Bases vary. The main tempo for bases are 140 BPM.