The Blade of Stealth

First Hidden Blade
Ever wondered when Hidden Blade was made for the first time?
It is not as simple as Samarians think. It is not a "gift" from Him whom Samarians believe in. This masterful weapon has a long tradition of use since hundreds of years ago. Starting with Darius. He was the man who kept Persia free of tyranny by forming a secret group. At that time, the king of Persia was King Xerxes I, a feared tyrant. Forging a Hidden Blade was simple, and he wore it on his right forearm. Darius then assassinated King Xerxes I and went on a journey to flee the Order of the Ancients, a group similar to our Templars.

Further expansion of use in the world
Darius first went to the Greek world to join forces with the mercenary Kassandra to fight off the invading Order of the Ancients in the Peloponnesian War. Kassandra was the first person to use the Hidden Blade under the left forearm for stealth.
Later on, the use of the Hidden Blade was extended in Egypt during the Ptolemaic Kingdom era. Aya, a descendant of Darius, acquired his Hidden Blade from Queen Cleopatra to help her take down the Order of the Ancients. Later, Bayek, her husband, was gifted this weapon while Aya crafted her own. Bayek was the first instance of a severed ring finger, which had become a tradition soon after. Aya and Bayek are the founders of the "Hidden Ones."

Vikings got their hands on it by killing a Hidden One and stealing it from him. It was then gifted to Eivor Varinsdottir, who used it the same way as Darius with the blade on top of their wrist.

Altaïr Ibn-La'Ahad became a mentor of the Levantine Brotherhood in 1191. With the inspiration from the Apple of Eden, he redesigned the Hidden Blade in such a way that it wasn't mandatory to sacrifice a ring finger.

In the 15th century, Leonardo da Vinci, with Ezio Auditore da Firenze, who provided pages from Altaïr's codex, made a few upgrades to the Hidden Blade, such as adding another one for the other arm. It was a concept from the 9th century. The second Hidden Blade was wielded only by Master Assassins, but it became more common later on.

Such a weapon should be wielded by skilled and dedicated assassins who have earned it.