Before the development of fabric to make bags, leather became one of the choices of raw materials. The leather is selected because it is durable, strong, easily shaped and widely available. Leather bags are very popular in the middle ages. As the times progressed, although the bags made from fabrics had expanded widely, leather bags remained to be one of the best. You can see some examples of leather bags, particularly in the form of briefcases, on www.blaxtonbags.com/collections/mens-briefcases.
Leather bags do have many advantages that many other kinds of bags do not. One of the advantages is the strength. The strength of the leather bag depends on the source of the animal skin used and the tanning process on different skin types. The sheepskin tends to be weak and thin, while cow skin tends to be thick and stiff. Compared to sheepskin, cow leather is thicker so it tends to be stronger. In addition to sheepskin and cowhide, there are also other kinds of leathers such as crocodile skin, and snake skin.