Witcher has an elven race Aen Sidhe, and GoT's white walkers are like sidhe made of ice, both derived from Ao Si in Irish mythology. Political and sexual intrigue, although since Witcher centers around one individual and his destiny, the political aspects are perhaps not as elaborate as GoT.
Some of them are built out of fan theories I read about GoT as well. And what I'll be talking about here are the striking similarities on some of the plotlines of Witcher and Game of Thrones. I have not read the ASOIF books, but I am an avid follower of the show and hence believe I have an idea of the major keypoints of the show.