London-based developer Firefly Studios has announced plans for Stronghold Kingdoms, which they describe as the world’s first castle-based MMO.

“What is exciting about Stronghold Kingdoms is not only are we taking Stronghold online and massively multiplayer, but we are funding this ourselves as an independent developer”, said Firefly CEO Eric Ouellette.

The new game is based on the ongoing Stronghold franchise, which has sold 5 million units since the first game in 2001.