I thoroughly enjoyed reading about life in the 1670s, but it wouldn't have been much fun living through it. So much research didn't make it into the short story, but it gave my characters a grounding and from there I could move forward.
In Scotland, things were pretty grim. Make one political mistake and you'd lose your lands and chattels. If you were on the winning side, you'd get your share of the spoils.
That's how the Beaumont family came to occupy (the fictional) Halkirkie Castle. They were English and were given Halkirkie Castle and the title of Duke as a reward for success in battle. However, the ties to England would have been very strong, so it's natural they would leave the 'miserable' winters and head south.
As the youngest of five sons, Charles would have received little or no inheritance, so he would have needed to marry a rich heiress, or find a way to make his fortune. Joining the military would have been a smart move - if he survived, he'd get a share of the spoils and could become very rich.
When Charles decides to remain in Halkirkie for the winter, he finds the castle transformed into a gambling den. Hmmm, gambling. Now there's an idea!