why does my GPS not work in Italy without WiFi? Currently travelling at the moment with my Asus Transformer tf300tg.

I don't have a sim card in it, but whenever I have WIFI access, I'll download the Google Offline maps and this is convenient cause when I need it, I can just load up the maps and use GPS to pinpoint exactly where I am.

This is at least what I've been doing in Slovenia and Croatia which has worked fine.

However, I've recently entered Italy and for some reason, although my Offline Maps are still there, I cannot use GPS to pinpoint my location anymore. It just keeps saying my location cannot be resolved.

Why is this? How exactly was my tablet resolving my GPS in the first place? It had no sim card and I was in some fairly remote places so it's safe to say that I wasn't using any mobile towers to detect my location. If that's true, then it's using pure GPS from the satellites, then if that's true, why has it suddenly stopped working once we've entered Italy?
The GPS should eventually work without wifi, the further you are in distance and time from the last GPS sync, the longer the startup time will be.   Perhaps in Slovenia and Croatia you used it enough that the startup time was reasonable.  (Wifi access can shortcut the process by giving the GPS a hint as to your probably location).

I would suggest putting the tablet somewhere stationary with a clear view of the sky and giving it a good while to sync, it will probably eventually sync up.