In 1926, the founder of Rolex, Hans Wilsdorf, founded a company based on the idea that Rolex-style and reliability could be brought to customers at a more modest price. Instead of using in-house Rolex-made movements, Tudor watches utilize other high quality Swiss-made movements. While some Tudor watches are similar to Rolex models, others are designed expressly for more youthful buyers who are just entering the prestigious and exclusive world of Rolex.
|Tudor Prince - Photo By Sputniktilt (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons|
If you'd like to read more about the business background of Tudor and the re-introduction of Tudor to the American market, here is a good article on Forbes:
Watch Out America, Tudor Has Arrived (Again) to Invade Your Wrists
If you are looking for a slightly different entry into the rich heritage of Rolex watches, Tudor-brand watches might be a more nuanced choice.