Highland Fling

Question: Were the Tuatha worshipped in Scotland as well as Ireland? I know that culturally Scotland and Ireland have a lot in common, but does that extend to their gods? (The question was brought on by watching Brave for like the 50th time and wondering who I’d make Merida a Scion of.)

Yep, they definitely were. Various Celtic gods are widespread across Scotland, and the Tuatha are the most major group of them, although their names are often slightly altered by the local dialects. Irish settlers crossed the water to Scotland around the second or third century and brought their deities with them, to mix with local figures as well as other imports from the Norse and even the Romans. Scotland's a giant melting pot that way, and is itself a mystical destination in several Irish legends, including the tale of Muireartach, the one-eyed goddess of the sea crossing between Ireland and Scotland who the Fianna claimed sometimes crossed the water to fight in their battles, or the story of Cu Chulainn traveling to Scotland to train under Scathach, the most demanding warrior woman known to the Irish.

Scotland does have a few figures that were probably deities of the local peoples, but for the most part their mythologies are imported from other nearby areas, and the Tuatha are the primary contenders when it comes to foreign gods with power in the area. If you're planning to mess around with the interplay between Scottish and Irish gods, you might be able to get some very interesting stories out of who came first, who took what territory from whom, and what kinds of political dynamics still remain in the area.

Personally, if I were statting Merida, I would probably set her up as a Scion of Scathach. I could see her running circles around Cu Chulainn at the same Legend level.