Regions are geographic areas on the game map that unlock as players reach certain milestones. As new regions unlock, new gameplay features and activities are unlocked as well. Regions can in many ways be considered levels, or Land - the higher a player's level, the more Regions that player will have unlocked, and the more gameplay activities will be available to that player.
Players competing in Limited-Time Events are competing with players in a particular Region - the more advanced the Region, the higher the rewards but the stiffer the competition.
All players initially start out in the same Region.