Raikage

The Raikage, translating to Lightning (rai) Shadow (kage), is one of the five great Kages of the Naruto world. It is unknown how many Raikages there were in the past, or even who the current Raikage is. The Raikage is the leader of Kumogakure.

First Raikage

 * Age: Unknown (Deceased)
 * Name: Unknown

The First Raikage was probably the founder or one of the founders of Kumogakure.

Second Raikage

 * Age: Unknown (Deceased)
 * Name: Unknown

The Second Raikage was the leader of Kumogakure after the First Raikage. Nothing else is known.

Third Raikage

 * Age: Unknown (Deceased)
 * Name: Unknown

The Third Raikage was the leader of Kumogakure after the Second and the village leader at the time when they started a peace contract between the countries with Konohagakure. The contract was just a cover for Gashira to try to steal Hinata Hyuga to find out of the Byakugan.

Fourth Raikage

 * Age: Unknown
 * Name: Unknown

The Fourth Raikage is the current leader of Kumogakure. He seems to have been the strongest Raikage ever, but it's unknown if that's true.