Ancient Egypt spans ~ 3,500 years from a pre-dynastic era beginning ~ 3,500 BC (BCE) to the Old Kingdom, 1st Intermediate Period, Middle Kingdom, 2nd Intermediate Period, New Kingdom, and post-dynastic era ending at 30 BC, concurrent with the death of Cleopatra VII. Hence, with over 5,000 years of recorded events, Egypt is the oldest known country whose civilization was based on a polytheistic religion and myths. It is the first true nation with political unification in ~ 2925 BC under Menes/Narmer with a putative first Pharaoh (king) named Aha in the capital at Memphis. The ancient Egyptians called their country Kemet (black land) for the dark soil deposition caused by yearly inundation of the Nile River.
Pharaoh was deemed a king and a god who was not only the leader of the country politically but the living Horus who became Osiris in death. He acted as the high priest for all the gods, though in practice he appointed others to carry on in daily ritual functions. He was the administrator of ma'at which was justice and stability as given to man by the gods. The chronological lists of pharaohs are derived from the Palermo Stone, the Turin Kinglist, and especially the compilation by Manetho, an Egyptian priest who lived at the beginning of the Ptolemaic Era (~ 300 BC). These lists were written in hieroglyphics that could be read by the 1920's after Champolion deciphered the Rosetta Stone, which was discovered in 1799. It should be mentioned that this written language has consonants but no vowels; hence, one must guess as to the exact spelling and pronunciation of words. For example it may be Re or Ra and pronounced "ray" or "rah".
Time as a cyclical event was fundamental to the Egyptians who believed in the transformation and resurrection in a "heaven" of only the pharaoh in the Old Kingdom but was democratized to include all by the Middle Kingdom. The symbolic rejuvenation was perhaps associated with the yearly inundation of the land by the Nile.
Gods and goddesses were numerous and when similar in purpose but from different sites with different names, Egyptians developed syncretism (merging) as functional reconciliation. For example Ptah was the creator god in the Memphite cosmogony, while Atum created the world in the Heliopolitan cosmogony. The Egyptians thought that both were different aspects of the same deity. The sun god Re (Ra) was frequently associated with many deities because of his universal nature. The Egyptian pantheon evolved into a complex of many deities, some theriomorphic (beast/animal like) or therianthropic (beast and human like). For examples, Horus was in the form of a hawk, while Anubis had a human body with the head of a jackal. Interestingly the ba, a principal form of the soul, was a hawk's body with the head of the departed human.
Temples were the focus of community worship and became centers of major economic and political functions. A local temple had a sanctuary for a local deity and all represented the Egyptian cosmos on a miniature scale with a ceiling decorated with stars, pillars in the form of lotus and papyrus and a raised sanctuary to represent the primordial mound above the primordial marsh.
Influence on other religions was considerable. Eastern religion stemmed from early Sumerian and Egyptian sources, but it was the latter that eventually had effect on Hellenistic religion and further on Roman adaptations and ultimately Judeo-Christian beliefs. See "Britannica" section. One example of how early mid-eastern myths were adopted into religious tenets is in the story of Moses, which was probably taken from the 1000-year earlier legend of Sargon I of Akkade (~ 2300 BC), which can now be read from the cuneiform. Plutarch (46-125 AD), a Romanized Greek, wrote in his Moralia (Customs and Mores) the story of how the Isis/baby Horus story was adapted to the Mary/baby Jesus story in early Christianity. As an aside, it can be remarked that Plutarch's writings had a great influence on Ralph Waldo Emerson and the Transcendentalists. The similitude of Isis/Horus and Mary/Jesus was recalled in more modern times in Frazer's "The Golden Bough" and recently in Kenneth Davis's CDs on mythology. As an aside, it can be remarked that Davis also notes that prototypic versions of the Lord's Prayer can be found in prayers written to such primary Egyptian gods as Re.
Creation myths were of four versions and connected to different cities and times. The main theme is that the primordial god of chaos Nun masturbated to beget a sequence that became the ennead (Greek for nine) that includes Shu and Tefnut who begat Geb and Nut who begat Osiris, Set(h), Isis, and Nephthys. In the rather common brother/sister relations, Osiris and Isis begat Horus and Osiris and Nephthys begat Anubis.
Concepts of the afterlife, heaven, and hell that are in current vogue among major religions of today, especially in Judeo-Christian beliefs derive with varying modifications from the ancient Egyptian theology. "The Pyramid Texts", composed by the priests of Heliopolis for the tombs of the 5th dynasty (~ 2600 to 2300 BC), notably in the tomb of Pharaoh Unas who ruled from 2356-2323 BC, were the historical record of an idea of heaven and hell. This invention has been of the highest significance in subsequent moral control, and in Egyptian society was to support the monarchy. In the different versions of The Pyramid Texts a common thread is the ascension of the pharaoh to the sky as the realm of the afterlife, which is dominated by the sun-god Re. The text communicates knowledge to the pharaoh of the customs and places in the hereafter, including warnings of places to avoid. The waterways of heaven are navigated by boat, so the king is dependent on a ferryman. In this journey after death, the king has become associated with Osiris, ruler of the underworld, and is transmogrified to a Horus-like rebirth. Consider parallels in other beliefs of heaven in the sky, hell as a place to avoid, and Charon in Greek mythology as the boatman who ferries souls of the dead across the river Styx to Hades. The so-called "Coffin Texts (~ 2000 BC) and "Book of the Dead" (~ 1580-1350 BC) known to the Egyptians as "The Book of Coming Forth by Day" elaborate on some points and include magic spells and passwords deemed helpful to those who travel the underworld. In "The Book of Gates" there is the implication that some people will pass through unharmed but others will suffer torment in a lake of fire (hell). The Amduat, called the "Book of the Secret Chamber" by the Egyptians, is the earliest of all funerary texts and documents the sun god's, and later the pharaoh's, journey through the 12 divisions (hours) of the underworld. The "Book of the Heavens" developed during the late New Kingdom, is a number of books and relates to "The Book of the Celestial Cow", which begins with the destruction of mankind by a great flood and is similar to the later story of Noah and the Ark.
The Concept of Soul clearly derives from the more complex Egyptian use of Ren (name), Sekhem (energy/power), Akh (ghost), Ba (personality), Ka (corporal presence/life force), Sheut (shadow), and Sekhu (remains/physical body), but these were mainly condensed to a combination of Akh, Ba, and Ka. The Ba is now regarded as the closest to the Western notion of soul.
Intrusion of Other Religions into the classic Egyptian ways of belief can be noted with the beginnings of the Coptic Church (from Greek Aegyptos) that has been attributed to the Apostle Mark who came to Alexandria, Egypt in the middle of the 1st century AD; this led to an early Christian merger with some remaining aspects of the ancient Egyptian beliefs. One interesting change in a symbol was the alteration of the Ankh to a cross. Around 600 AD, Egypt was conquered by Arabs, and Islam became the dominant religion and remains so today.
In summary, many of the biblical stories dealing with life after death derive from ancient Egyptian religion. As Joseph Campbell details in his treatment of transformation of myths through time, the human's apparent need for hope in the hereafter leads to many convergent stories that are an integral part of religion even today. Given the extensive borrowing of early human-imagined myths and religions to form the derivatives that are practiced today, the intolerance often shown by one sect toward another is a sad commentary on humankind. It is surely an example of arrogance based on ignorance that leads any group to send missionaries to convert those who have different religions that have evolved to suit their lives.
Our Heritage of Religious Beliefs from Ancient Egypt