Sixteen teams were invited to the first International in 2011. Valve announced the tournament as Dota 2’s debut competitive championship and assembled a field of leading teams from the emerging global DotA scene.
The event was held during Gamescom in Cologne from August 17 to 21, 2011. It was designed not only as a tournament but also as the first public viewing of Dota 2, giving spectators a chance to see Valve’s standalone sequel in action.
The competition used a group stage followed by a double-elimination bracket. Teams were divided into four groups; group winners advanced to the winner’s bracket, while the remaining teams entered the loser’s bracket.
The inaugural field is easy to confuse with later editions, because The International’s qualification systems changed repeatedly. Later tournaments used combinations of direct invitations, regional qualifiers, wild cards, and eventually broader qualification formats. The first event, however, is specifically recorded as having 16 invited teams.