Cogman is a familiar name to fans of Game of Thrones, as he's served as a producer on the show since the very beginning.
Just when we [die-hard fans] were mourning life after Game of Thrones' latest season came to an end, there's a beacon of hope with HBO writers gearing up for the show's prequel series. The show that [co-showrunners David Benioff and Dan Weiss] have created will get its proper send off first.
HBO and Martin are maintaining secrecy about the exact plot details for each of the shows, except to confirm that they will all be prequels, rather than sequels.
The writer for the rumoured fifth Game of Thrones prequel has been announced - and it's GoT's veteran writer and executive producer Bryan Cogman.
This fifth project is also being worked on by George R.R. Martin.More news: Walmart tests out new delivery service
Martin hinted at Cogman's fifth prequel in a post to his LiveJournal page this past May. Cogman developed the project by working closely with author George R.R. Martin, who cryptically referenced the existence of an additional unconfirmed prequel on his blog months ago (and has now added some new comments on his blog, below). Episodes written by Cogman include season 7's "Stormborn", season 4's "The Laws of Gods and Men" and season 3's "Kissed by Fire". He thinks that two or three could reach the pilot stage with the possibility of one emerging sometime in 2019 or 2020. Jane Goldman, Carly Wray, Max Borenstein, and Brian Helgeland are also working on potential spinoffs, and all are also collaborating with Martin.
People have already began to speculate what the prequels shows could focus on, with many suggesting that they would like to see Robert's Rebellion, a period of time that is regularly mentioned in the current series.
Game of Thrones has yet to finish its final season on HBO, so the network has a lot of time to go through all of its prequel pitches and pick the best ones for production.
That being said, there are dozens upon dozens of other stories throughout the history of Westeros that could be used for these "Game of Thrones" series.