The development of shoes is as varied as why they were used. Since the dawn of time, they were designed and developed for mostly Military use. From heavy Sandals to a variety of boots, shoe wear evolved with Man's need. The Sanatorium Shoe was a first step in total foot coverage, to protect the feet (somewhat against the elements). Seen in varying forms from the 10th Century up to the 13th, they were based on the Armor component called The Sabaton. Designed to protect the foot of a Knight on foot or horseback, the shape was copied in leather.
Few surviving examples were roughly 1-inch thick and featured a type of doubled leather sole, to help with wear and tear of the outer sole. Variations experimented with cut ventilation to keep the foot dry from perspiration. They also had the unfortunate side defect of not being waterproof. They were side laced with strips of leather tongs to ensure a proper fit.
Worn with a form of woolen Sock, The Sabaton Shoe was worn by Noblemen and Royalty (due to the expense in making them).