According to the Japanese history, a ninja was a specially trained warrior. During this training he learned several unorthodox arts of war.

This kind of soldiers was extremely respected and feared. Their methods included assassination, espionage, martial arts and scouting.

Traditionally they were trained for dangerous and secret missions. Their origins are mysterious. They aimed at causing chaos in enemy territory.

They were hired by daimyos, shoguns, who paid them for the missions they had to execute.

The ninjas firstly appeared during the 15th Japan, in the regions of Iga and Koga (in central Japan). At that time the country experienced troubles and conflicts almost everywhere.

That s why the action of the ninja became important. Their strategy was to practice the guerrilla warfare and undercover espionage operations. They achieved to solve many battles like this.

This method was criticized but avoided frontal assaults. Ninjas were not only spies they were also accomplished warriors, as the samurais were.

Some daimyos and shoguns were suspected of being secretly ninjas. Until now no clues proved definitely this theory.

At their early beginnings the ninja groups were small and structured around families and villages. Later they developed a hierarchical organization.

It seems that even women could be ninja. Once again there are no evidences to justify this theory.

Nowadays they remain a subject of controversy. Their existence is made of mystery and secrets.