Castle or Manor?

I'm working on that period romance piece I've told you all about. I originally wrote this rough draft years and years ago, before I started doing so much research into my books. Throughout the book, I called the location the duke and the main character live a manor. However, I started wondering the difference between a manor and a castle in Scotland pre-Culloden. (Time frame reference for you Outlander fans.)

It turns out fortification is the difference. If the estate has walls and defenses it's a castle. If it's just a landed estate, it's a manor. Good to know. It also means I have to change every reference to a manor in my book to a castle.

Research is important. I want my books to be historically accurate for the time period. Thankfully, I don't need to drag out copies of Encyclopedia Britannica (who remembers those from their childhood?). Instead, I can fire up Google and start down the rabbit hole.