Kumogakure, or Hidden Cloud Village, is located in the Land of Lightning. As one of the five great Ninja villages, Kumogakure has a Kage as leader, the Raikage. In that past, Konohagakure and Kumogakure were at war, and during peace talks, one of the ninja from this village tried to kidnap Hinata Hyuga, which resulted in an incident that ended with the death of Neji Hyuga's father. Nothing apart from that is known about it at this point, but it stands to reason that its ninja specialize in lightning-based jutsu.