What's that in Corfu?
Are you going to push into the steppes until the GH is no more? Or is the main goal to form Italy and recreate the Roman empire?
The Golden Horde is being a bad boy, it realised that you had peasants rebelling against your rule and then decided to attack!
Hope you'll stay Ferrara - Italy blobs are a somewhat common sight, and Italy's has about the ugliest tone of green there is. Kazakh or Pommerania green... much better, but doesn't compare to huge Ferrara
To add to the point of History_Buff, nationalism wasn't really a thing back then if compared to the 1800's. To put things in perspective, Rome wasn't called the republic of Italy, it was called Rome or SPQR despite the large swaths of land. Ferrara's king wouldn't just abandon his title to create the kingdom of Italy, he'd much rather create the EMPIRE OF FERRARA! Which it kind of already is.
Bluntly, I would say, stay as the glorious nation of Ferrara!
Also, what about Inflation, I can imagine you had to mint quite a bit to supports those armies and colonizing GH...Just wondering, what is your tech like?