Simply put, Cognac is distilled wine, but it's not that simple. In order for an Eau de Vie de Vin to be called Cognac, it has to comply with a lot of rules. The most important ones are: the distillation must take place in an Alambic Charantais made entirely of copper. Of course, the distillation must take place in the Cognac region. The distillate must be aged for a minimum of 2.5 years in French oak barrels made from the oak that grows in Limousin or Troncais.