I am currently reading a great book about the history of calculus, which, given salon’s interest in math, I might summarize here. : ) Meanwhile, I will give you the Frederician tidbit that Leonhard Euler (super important and influential mathematician) first worked in Saint Petersburg, but in 1741, Fritz offered him a job as director of his astronomical observatory. The book claims that Fritz was deeply disappointed with Euler who lacked the flair of Voltaire and several of his other collected intellectuals. Euler, in turn, was frustrated by the time-consuming tasks to which he was assigned. In 1766 he moved back to Saint Petersburg and Catherine the Great, who offered him a position where he was more free to do the math he wanted. No sources for any of this, though.