In feudal days of old, lower ranked samurai took the heads severed from the bodies of foes killed on the battlefield to their commanders for identification called "Kubi jikken"; this activity took place because a severed head was crucial piece of identification evidence leading to conferring of honors on lower ranking samurai.
首実検（くびじっけん）とは、前近代、配下の武士が戦場で討ちとった敵方の首級（くび・しるし）の身元を大将が判定し、その配下の武士の論功行賞の重要な判定材料とするために行われた作業。