Muse

Hi everyone! I have a Latin-related question that has been buggering me for a long time now, maybe some of you could help me out? (And yes, I have tried google many MANY times, but haven't come up with an answer yet.. :-/ ) This is the question; How did Latin spread through trade? I know many traders learned the language by selling their wares to the roman military, but I’m guessing there were a lot more possibilities for traders to learn Latin. Also, how did the language spread from those traders to other non-latin speaking communities? Could you help me out please? (Or help me find some usefull links?) Thanks!