The plot rotates around twin blades given by old king to his two sons. The swords are leaf-shaped, about 3 ft long and made of steel. This is a dual anachronism:
1. Blade shape is wrong. Egyptian royalty at this time had a distinct melee weapon called khopesh - a sickle-shaped broadsword, that had a single slashing edge. Leaf blades were not used in Egypt in the 2nd millennium BC, they are a distinct feature of Celtic smiths of the Bronze Age.
2. Blade metal is wrong. At this time the only material used for blades was bronze - it's still Bronze Age. First reliable evidence of iron metallurgy appears only a few centuries later, circa 11th cent BC. Iron blades 3 ft long required amount of metal and technologies that became available no sooner than 8th cent. BC. Steel of quality shown on screen appears only in 8-9th cent. AD - 2000 years after the film events.
The Great Sphinx of Giza appears in one scene, looking very much like it does today. However at the time of Moses the Sphinx would likely have still had its nose, although we do not know when exactly it was lost. While the common story about Napoleon's soldiers using the Sphinx as a target for shooting practice (thus breaking off its nose) is proved to be untrue, there is no proof as to when the Sphinx lost its nose. There is a story about a ruler damaging the Sphinx in the 14th century, but the historian mentioning it also mentions the destruction of the ears (which clearly did not happen, therefore casting doubt on the whole story). The only thing we know for a fact is that the nose was gone by 1737 when British artist and marine architect Norden sketched the Sphinx without its nose.
The funeral service for the old Pharaoh seems to be taking place in Abu Simbel - this was built during the reign of Ramses II, so couldn't exist yet when his father dies. The battle of Kadesh was later in his reign not before he became Pharaoh.
The film shows Jews building pyramids. The last pyramid was built for Ahmose I ca 1525 BCE. The Jews didn't arrive in Egypt until the mid-1200's BCE if Ramses II was actually the pharaoh of the Exodus.
Moses says he's grandson of Horemheb. If this were true, either his mother would have been the 18th dynasty pharaoh daughter and likely be the wife of the current pharaoh, certainly not his sister. Or Moses couldn't be the grandson of Horemheb.
The scenes where Moses crosses the Red Sea were shot on the beach of Cofete (Fuerteventura). If you take a careful look at the backgrounds before he leaves you'll see that Moses actually arrives in the same place where he left. They just shot the first scenes with a view to the north and most of the later scenes with a view to the south. Nevertheless you will see a few backgrounds that are identical.
When Nun first tells Moses about the prophecy of his birth and how he came to live in the palace, he tells Moses only the first born males were ordered killed. Moses, however, is the youngest child; his older siblings are Aaron and Miriam - whom Nun even mentions when he tells Moses who he really is, and that Miriam placed him in a basket into the Nile. The actual edict was that all male Hebrews be drowned.
The Biblical Exodus, if it ever did happen, certainly did not occur in the reign of Ramesses II. Whereas the Pharaoh of the Exodus was a relatively-weak leader and had a short, briefly-prosperous reign that turned disastrous, Ramesses II was one of the strongest, most successful, and long-lived Pharaohs of Ancient Egypt. There is also no evidence of either the plagues or of any pursuit of escaping slaves led by him, and almost all of the events of the Exodus cannot be reconciled with his reign or time period.
Hanging as a means of execution was non-existent in ancient Egypt where drowning, beheading and crucifixion were common. There is no historic record of any circumstance that could produce explosions as depicted in the Hebrew arson scene.
Although the movie was criticized for white-washing, Ancient Egyptians were not ethnically similar to modern Sub-Saharan Africans. Their genetic make-up was more similar to Semitic, Turkish, and European populations. Specifically Ramses II was a white red-head, as were half of his close family. (see Ramses II's mummy, his family's mummies, which still exist, and the latest DNA studies on Ancient Egyptian demographics).
Camels were present in Egypt since the Early Dynastic Period (3150-2686 BC) which ended over a thousand years before the reign of Ramesses II. When historians say that camels were introduced in "North Africa" by the Romans, they actually mean in the Maghreb (modern Morocco, Algeria and Tunisia), which the Romans called Africa (Tunisia and eastern Algeria) and Mauritania (Morocco and western Algeria).