Description: Kabuto, which is known as a samurai helmet, first appeared in the 10th century Heian period. In the Edo period, when society became peaceful, armor with a revival of the medieval times became popular, kabutos were made again.
Kabuto are often adorned with crests using four types of decorations such as the maedate (frontal decoration), wakidate (side decorations), kashiradate (top decoration), and ushirodate (rear decoration). These can be family crests or sculptural objects representing animals, mythical entities or other symbols. Horns are particularly common, and many kabuto incorporate kuwagata, stylized antlers like here.
The kabuto was an important part of the equipment of the samurai, and played a symbolic role as well, which may explain the many Japanese expressions, sayings and codes related to them.

References:
Arms and Armor of the Samurai, Ian Bottomley, Anthony Hopson Random House Value Publishing, 1993