On occasion, and to my great surprise, my own series, Dark Tales of Randamor the Recluse, has been compared to Games of Thrones. More specifically as a gay version of Martin’s far more successful series.
It always annoyed me, whether the comparison was meant in a flattering way or not (more often not), because there was no way I could have been influenced by George R.R. Martin's series. I never read it, nor have I seen the TV series. I did read the description of a few events occurring in Martin’s books, and I recognized some of the themes because I had used them myself.
Where the similarities just coincidences? I think I've solved the mystery. You can read more in this blogpost on my website.