Skulls are a symbol of death and mortality around the world, and historians have documented the use of skulls for decoration as early as 7200 BCE in the Middle East. Skull art also has widespread roots in Latin America, starting with the Aztecs in 1200 BCE who built skull racks and later used them prominently in their Day of the Dead Ceremony. Skulls also entered European imagery in the mid 13th century, after the Bubonic plague decimated the continent.
In Aztec culture, the skull was considered to be at the center of the universe, and skeletal imagery often found its way into stone carving. In the Tonalamatl, a famous calendar carved in stone, the skull was positioned at the center of the 18 month cycle. After the Spanish invasion of Mesoamerica, the skull was purposefully eradicated by Europeans as a pagan and savage symbol of the conquered people.
In Europe, skull imagery was most commonly used as a reminder of death and the short duration of life. Starting with the 15th century, skulls and bones were often used to decorate churches, and the practice persisted as late as the 19th century in some parts.
The use of skull imagery made a ressurgence in Western art in the 20th century, with artists such as Georgia O'Keefe, Albert Potter, and even Andy Warhol using them in unsettling and thought-provoking ways.