Y'ffre was made to be in charge of Bosmer so he made the wood people to always to be wild in the forests but never really beasts. According to a Khajiit legend 'The Words of Clan Mother Ahnissi' the god Nirni made the deserts hot and sandy and the forests wet and filled with poisons. This agreement is known as the Green Pact. However, they didn't forget Y'ffre, the Forest God and in return for his kind patronage and gave him a permanent promise to never kill, injure, destory or harm the flora of their new home. They were so naturally good at it that they become wild themselves. So Bosmeri began to change themselves to fit the surroundings. When the first elves arrived to Valenwood the forest was so dense and inhabited by so many feral creatures that no man or mer for that matter could change it. They naturally adapt to this weapon by snatching and firing arrows in one continuous motion. Some folks even believe that Bosmer have invented the bow. However the area where they excel the most is archery. These characteristics make them one of the bests scouts and thieves in all Tamriel. As the Bosmer adapted to the life in woods, their appearance changed from typical Altmer - they are much shorter and their skin color allows them to visually merge with forested areas. In fact they understand animals so well they can convince even the wildest beast to fight on their side. The wood elves prefer a more simple lifestyle and being in harmony with the savage lands and feral forest creatures. Their wild hearts find such practices too formal and stiff. Unlike their cousins Altmer and Dunmer, Bosmer are not into the arcane arts. The wild almost barbaric vitality of Bosmer rightly makes them the rulers of forests. The 'Bosmer' and 'Boiche' in the wood elf language means 'Tree Sap People' and that is how they call themselves. Bosmer are cousins to Altmer or High Elves and Dunmer, the Dark Elves.

They are one of the elven or mer races in Skyrim.

Where to find elven armor in skyrim