During the Middle Ages, buttons were made from glass and were incredibly expensive; but not only were the wealthiest people the only ones who could afford them, they were the only ones allowed to wear them.
The fifteenth century saw the birth of sumptuary laws—laws that regulated consumption. Although originally brought about in an attempt to balance import trading by limiting the market for expensive imported materials, they became laws that regulated and reinforced social rank and privilege.
In England, the sumptuary laws dictated the color and types of clothing that each social rank was allowed to wear, including furs, fabrics, and accessories—like buttons. Laboriously long lists of items for each sex were issued and specified everything from materials to where the item was manufactured. Queen Elizabeth I issued a number of sumptuary laws to try to reduce Britons spending money on foreign merchandise and to ensure that people did not dress above their station—even if the person could afford it. Buttons being expensive (many were made abroad), everyone except the very wealthiest were banned from wearing them.
Needless to say, these laws were largely ignored by the people and poorly—if ever—enforced by the law; even so, sumptuary laws continued and were even brought to the states. In Colonial America, a law was put in place that only people with a fortune of at least 200 pounds were permitted to wear lace, ruffles, belts, capes—and yes, buttons.