Quote Originally Posted by MikeV View Post
The Europe and India theaters are linked by Persia -- for example, if you start in India and scroll the strat map north-west, through the Persian regions, you can continue on into Europe (the reverse is also true). The mini-map changes its theater display, at some point.

This makes the Persian regions strategically interesting, by virtue of being the only 2-theater land location. It suggests overland trade routes to/from India, for example.
You can't transport goods overland to Europe via Persia. At least, not all the way. I found this out in my Maratha campaign. I got a trade agreement with the Ottomans. However, the Russians were blockading the port in Constantinople. This cut off my trade route. The goods would go via land to the province NEXT to Constantinople, they have to be transported overseas to Constantinople.