The first Ju-Jitsu schools appeared in Japan in 1532, the earliest is Takenouchi Ryu. Originally, in the 16th century, there was little to distinguish primitive Ju-Jitsu from indigenous Sumo, or Kumi-uchi (battlefield combat) but by the end of the Muromachi period (AD 1600) there was a clear separation between the two.

The fighting system which was taught had developed out of battlefield survival techniques and was known by other names, including wa (harmony) and yawara (hand to hand fighting). Given that in battle the majority of opponents were armoured, arm-locks, throws and strangles were considered to be more practical than kicks and punches. The throwing techniques of Ju-Jitsu developed from fighting techniques rather than from sport. Hand to hand techniques were developed for close combat, with throwing and grappling being used in order to disarm and immobilise an enemy, which was particularity vital. Another factor, which affected the development of techniques, was the type of weapon the warrior was likely to find himself confronted with. The control of the arm holding the weapon was favoured as the way to deal with stabbing attacks, and hara-gatame and waki-gatame can be attributed to need to disarm swordsmen or warriors armed with knives. The wearing of armour and the muddy, slippery nature of most battlefields also explain the surprising number of sacrifice throws, or sutemi waza which are often regarded as inherently perilous techniques in combat sport.
 
On a blood-soaked, muddy battlefield, where it was difficult to keep one's balance, it was important to go to the ground with an advantage, and sutemi waza provided the means of turning the tables before impact, and so getting on top of an enemy. 120 years later other names were given to what was being taught, including Tai jitsu (body techniques) and kempo (a character reading kung fu in Chinese).
 
Many of those practising Ju-Jitsu were bushi, warriors who were not samurai aristocrats, and who were increasingly interested in striking techniques which could be used against unarmed attackers, such as pea sent robbers or belligerent drunks. Killing people in brawls were as illegal then as it is now, so less than lethal techniques were needed for dealing with such confrontations. Ju-Jitsu expanded in this period and the techniques, which grew in popularity then, have more in common with those being practised today, as they were intended for self protection rather that a battlefield fight to the death. These techniques work just as well in the car park or the pub as they did on the street of medieval Japan.