Historically, Deerskin Leather was originally used by Native Americans and the American frontier culture for clothing and yes- footwear.
The physical structure of deerskin leather is different from other types of leathers. Technically speaking, its elongated interwoven fibers give it an extremely high shear strength and abrasion resistance. The spaces between the fibers make the leather soft and comfortable over a wider range of temperatures than others. In other words, this means that it is cooler in the warm weather and warmer in the cold weather.
Being a lightweight and thin leather also ensures that deerskin has stretch and offers excellent dexterity. Another popular benefit of deerskin leather is that even when it gets wet and dries, the soft texture and flexibility still remains - one of the many reasons it makes for an excellent choice for a comfortable insole.
Deerskin is one of the most difficult leathers to work with, both in its tanning process, and in the making of leather goods. However, when done properly however, it produces one of the strongest, softest, most durable, and comfortable leather around.