Around the beginning of this year, I started reading a really interesting non-fiction book about 11th century Britain, and inspired me to make a fantasy book roughly based on it. I had a whole lot of characters sorted out and rough plot ideas, but then, several months later, after first coming up with the concept, I began watching the Game of Thrones series. I was very dismayed to find that the series had striking similarities to my own idea, even though I'd never even known about Game of Thrones, let alone know they were based on a book series some months later. What do I do? I had a concept of a noble family living in the north of the kingdom, were it's very cold and wild (based on the piety kingdom of Northumbria) which now just sounds like a rip off of the Stark family. I also thought of a character who was a princess in another neighboring country (based on wales), and has a claim to the throne of the other kingdoms, and wants to take it back. She also had a useless brother from whom would ultimately die, leaving her as the heir, and her symbol would be a dragon. But now, that just sounds exactly like Danerys from Game of Thrones. Plus, the whole basis of the books would be a long story, spanning many years, of a ruthless political battle between noble families. Sound familiar? Should I just ditch the whole idea, or should I keep working on it despite the similarities?