Thanks, Thought Bubble. So how did the Mongols help catapult Moscow and its princes to prominence? Well, first, they named Muscovite princes the Grand Prince on more than one occasion. More importantly, the Muscovite princes won, that is to say, purchased, the right to collect tribute on behalf of the Khan from other princes. That's a good gig, because it's easy to skim a little bit off the top before you send it down the line to the Mongols. Which is precisely what the Muscovite princes did to enrich themselves. One prince who was particularly good at this was known as Ivan Kalita, using my Russian I can tell you that that translates to Johnny Moneybags.