The World of Ice and Fire is a companion volume to the Song of Ice and Fire novels. The book is being written by Elio Garcia and Linda Antonsson in consultation with George R.R. Martin and will be published in the USA by Bantam. The text was finalised in April 2014. A provisional release date has been set for November 2014, dependant on when the book's remaining artwork is submitted.
Garcia and Antonsson are the webmasters and creators of Westeros.org, the largest online concordance of information on the series and also the site of its largest fan forum. Martin has already confirmed that he sometimes uses the existing online concordance to rapidly double-check information if he is away from his notes. He has joked that his co-authors know more about Westeros than he does. Garcia and Antonsson started work on the book in 2008, mostly writing it whilst Martin worked on the novels. Martin then added additional material and chapters after completing the fifth novel in the series.
The world book will be a companion volume to the series, consisting of sections on history, geography and heraldry. There will also be a substantial guide to both major and minor characters in the series, and original artwork throughout. Tolkien artist Ted Nasmith has already completed a number of portraits of the major castles of Westeros for the project. There will also be some new maps.
After finishing A Dance with Dragons, Martin started working on material for the world book. His expansion of the material for the Dance of Dragons grew extremely long, so he cut it and turned it into a novella, The Princess and the Queen, which will be published in his Dangerous Women anthology.