If you work your way around the 'circle of fifths' you work your may through all the major scales. For example, starting with C major if we add one sharp, F#, we get G major. Adding a second sharp, C#, gives us D major and a third, G#, A major. The way English speaking music students remember this is with the mnemonic:
Father Charles goes down and ends battle
(N.B. Going the other way, adding flats, follows the mnemonic "Battle ends and down goes Charles' father".)
What is the history of this mnemonic?