Formal mummification can be traced to the 4th dynasty of Ancient Egypt. Before that, the natural mummification of bodies occurred because of their burial in dry, Egyptian sand that preserved their bodies.
While the natural preservation of bodies took place due to the dry desert sands, more wealthy or noble Egyptians were buried in coffins or tombs to protect their bodies from animals. When it was discovered that the coffins and tombs did not preserve the bodies of their Pharaohs well, the process of formal mummification was created. The process took approximately 70 days and involved a series of extremely detailed, exacting steps to prevent any decomposition.