It is August 1971. Football teams from England, Argentina, Mexico, France, Denmark and Italy are gathering at Mexico City’s sun-drenched Azteca Stadium. The scale of the tournament is monumental: lavish sponsorship, extensive TV coverage, merchandise on every street corner and crowds of over 100,000 hollering fans turn this historic stadium into ‘a cauldron of noise and heat’ match after match. A fawning media treat the players like rock stars. The atmosphere is reminiscent of the greatest moments in international footballing history. But this is a tournament unlike anything that’s happened before. The players on the pitch are all women. And it’s likely you’ve never even heard of it. This is Copa 71, the unofficial Women’s World Cup. Dismissed by both FIFA and domestic football associations around the world, this event has been entirely written out of history. Until now.