Difference between Ninja & Samurai?
It was a Samurai that had a high-class reputation who that even in mortal combat he would adhere to the Bushido code of ethics, of the historic Japanese society. Ninjas on the other hand were outlaws, and lower-class peasants that fought with stealth, and no personal code of ethics to live by.
Some of the first known recorded female Samurai were known to be around A.D. 200. However, they were known as Onna-Bugeisha which means woman warrior. They spend years training in the martial arts and fighting alongside Samurai. Rather than the Sword, their favorite weapon is the naginata. This is a long pole with a sharp blade at the end.
Samurai saved heads
It was a ritual; necessity for Samurai to shave the top of their heads, as this allowed their helmets to fit better. During the battle time, this was an advantage. It wasn’t until the Meiji Period that Samurai were prohibited from wearing any type of armor or carrying a sword, and so the tradition
Japanese emperors died young
There were very few emperors in Japan that lived past their 40’s. Meiji Emperor’s had five predecessors, yet only his grandfather lived past 40, dying aged 46. 5 of the emperor’s brothers and sisters died really young, and only 5 of his 15 children from concubines reached adulthood. So the family had a really hard time with mortality. This wasn’t an unusual amount for many Lords.
You can read more about those, and the code of the Samurai here.