With House of the Dragon being the success that it has been, HBO is probably excited to get to work on more of the Game of Thrones spin-offs it has planned. Two of those, it turns out, may have just been cancelled, however.
House of the Dragon was a huge success for HBO. It pulled in similar numbers as Game of Thrones did in its later seasons and very quickly earned an official renewal for season 2. HBO had been planning for more Game of Thrones spin-offs since before the show had concluded, as the first show was one of HBO's tent pole successes and its ending threatened to leave a gap in HBO's line-up. Since the books on which the show is based on have plenty of other stories that could be adapted to the screen, HBO turned to the world of Westeros to find their next big tent pole series.
Both House of the Dragon and Game of Thrones were produced by Startling, Inc. Both series are listed on the website for company, alongside a few other projects set in the Game of Thrones universe. A prequel series titled Sea Snake/Nine Voyages, which was set to chronicle the youth of Corlys Velaryon (Steve Toussaint), has been removed from the "in development" tab on the site. Another titled Ten Thousand Ships was set to chronicle the travels of the Rhoynish Princess Nymeria as she led her people away from the Valyrian Empire and into Dorne. That has also been removed from the "in development" tab.
Other projects, however, are still listed as being in development. A series based on the Tales of Dunk and Egg novellas, titled simply Dunk & Egg, set about a hundred years before Game of Thrones, is still on the development slate. Another production, titled Harrenhal, A Song of Ice and Fire, is listed as a stage play. It likely covers the events preceding Robert's Rebellion, which involves a tourney held at Harrenhal where Lyanna Stark and Rhaegar Targaryen fell in love, chose to elope, and eventually had Jon Snow (Kit Harington).
Given that House of the Dragon has chosen to include the Prince That Was Promised prophecy and its accompanying Song of Ice and Fire, focusing on more Targaryen-based projects could mean that these two elements will be connective through lines in the Game of Thrones franchise. The success of House of the Dragon has likely led HBO to the conclusion that audiences want to see more Targaryen shows, and there's no shortage of stories involving Targaryens.
The status of the Jon Snow sequel series is unknown, as it was not previously listed under Startling, Inc.'s production schedule, so it's possible that the project is under some other company. If that show plays its cards right, it could definitely be a big hit for the network. Though the end of Game of Thrones proved controversial, the project might be one to win back the fans.
House of the Dragon and Game of Thrones are available to stream on HBO Max.
Source: Startling Inc.