In an interview with GamesIndustry, BioWare's Mark Darrah noted that when BioWare first started with the Frostbite engine, it was built as a multiplayer prototype.

Here's the quote:

"We actually had a project code-named Blackfoot which was the first game we had that was looking at Frostbite. It was a Dragon Age game, multiplayer only, that was in development before Dragon Age 2 came out. That became the core of what became Dragon Age Inquisition, the techlines, more than any of the development, so we’ve actually been looking at this a long time.

At its roots, role-playing is a multiplayer experience. It’s sitting at a table with your friends and playing a pen and paper experience. It’s been a single player experience on computers for a long time, but Baldur’s Gate had multiplayer co-op through the story. This is an attempt to get that feeling back, something you can do, get a fantasy experience, but much more bite-size.”