It should come as no surprise that EA wishes to continue the Battlefield series, but few have been expecting a game set during World War I. Maybe a return to World War II, maybe something set in the future, but The Great War? That wasn't what we were expecting. Nonetheless, this appear to be the case for Battlefield 5, which might have been exposed thanks to Swiss online store World of Games.
We expect the listing to be taken down shortly but for now the game is viewable for Playstation 4 and Xbox One, as well as the PC. The release date on the site is set to October 26th of this year, and the describtion reads "Mehrspieler Taktik Shooter im 1. Weltkrieg". In English that German phrase translate to something of the effet of "Multiplayer tactical shooter set in WW1".
It could be nothing, or it could be something. Of course, warfare during WW1 was entirely different that the more mobile and vehicular modern times that Battlefield has been exploring recently.