[Note: This interview discusses broader thematic details of the A Song of Ice and Fire series, especially its historical sources, as well as Martin's early experiences that led him to become a writer.]
http://www.abc.net.au/local/stories/2013/11/08/3887040.htm?site=conversations
http://www.austinchronicle.com/blogs/books/2013-08-29/lonestarcon-3-the-george-r-r-martin-interview/