Origin

• The history of swords in Japan goes back more than 2,000 years, the age of the earliest known metal sword, which was discovered in a Japanese grave. However, the katana didn't appear until the middle of the 10th century. It was created for mounted troops, most if not all of them noble or titled warriors, to use in battle.
  
  

Samurai

• As Japan evolved and became solidified as a country, the samurai grew more powerful as a class. The warrior caste of Japanese society, the samurai carried a daisho, which was a set of two blades. One was a katana, and the other was the wakizashi, a shorter sword. The katana was developed for the use of samurai, and it became a symbol to distinguish them. By 1600, samurai were the only people allowed to even handle these deadly blades.
  
  

Evolution

• While originally a sword designed strictly for warfare, the katana evolved into a status symbol. The sword was seen not only as a weapon but as a representation of the samurai's heart and soul. Blades were often passed down through generations, and it was seen as a great honor to receive the sword of a family member. It was between 1190 and 1337 that some of the finest swords were produced, some of which are currently on display in museums.
  
  

Decline

• After 1596, katanas as people traditionally think of them became very limited. A large part of this is because in the 1600s they were restricted to members of the samurai class. Blades were cut shorter during this period, and were referred to as furui katana.
  
  

The Modern Age

• Katanas which were made between 1868 and 1926 are referred to as showa katana. These were the first katana ever to be produced by machine instead of handmade by a swordsmith. After this time, the katana ceased to be a functional weapon, though many of them are still produced in Japan and around the world. The quality of many of these blades is extremely cheap, and it is a crime to remove a genuine katana from Japan without explicit government approval.