This sarcophagus, or coffin, including a base, lid, and mummy board, dates to the middle of the Twenty-first Dynasty (c. 1000-968 BC). The high priests of Amun at Thebes assumed rule over Egypt in the Twenty-first Dynasty, and a number of changes took place in funerary customs. Beginning during the Old Kingdom (2687-2191 BC), tombs were built of permanent materials and the interior walls of the tombs were decorated with scenes of daily life and funerary rituals. They were also inscribed with texts to further ensure that the deceased would travel from life into the afterlife, as well as to provide sustenance for the deceased in the afterlife. During the Twenty-first Dynasty, burials were made in plain underground chambers or rock crevices, and the surface of the coffin served as the replacement surface for the ornate scenes and texts previously found on the walls of the tombs. This type of sarcophagus is known as an anthropoid coffin. It is made of sycamore wood and shaped in the form of a human outline. The head, hands, and feet are modeled in high relief. The figure's plaited beard, also a reference to the god Osiris, most likely identifies it as a male's coffin. The space in the inscription on the lid's footboard that would have been reserved for the name of the coffin's owner has been left blank, leaving his identity a mystery. The sarcophagus and the process of mummification were central to ancient Egyptians' beliefs about the afterlife. According to Egyptian belief, the sun god Re descends into the underworld when the sun sets. Protective deities help him overcome the dangers threatening to impede his path to rebirth at dawn. The Egyptians believed that in the afterlife, the pharaohs became one with Re and were likewise reborn with him at sunrise. While only the pharaohs journeyed with Re through the nighttime hours, all Egyptians faced the same dangers on their journey to the afterlife. Instructions for the elaborate preparations necessary to safe passage from life into the afterlife were found in the Book of the Dead. When a ruler or a well-to-do Egyptian died, his or her body was embalmed and wrapped in linen in order to keep the deceased looking as much like the living body as possible, enabling the person's spirit (ka) to recognize and return to the body for the afterlife. This process, called mummification, associated the deceased with Osiris, the god of the underworld. As a precaution against the disintegration of the deceased's face, a substitute face was provided by depicting the face of the deceased on the coffin and also representing it on the inner lid (the mummy board). The other images on this sarcophagus are from the Book of the Dead. A number of deities are shown assisting the deceased on his or her voyage. By depicting images from the Book of the Dead in tombs, on papyri (paper made from the papyrus plant), and on sarcophagi, the Egyptians believed they could help produce the desired result-a successful voyage to the afterlife.