The temple organizations of ancient Egypt owned a great deal of property and possessed immense power in their own right. When the Pharaoh’s authority was strong, the power of the priesthood tended to be suppressed; such as during the Old Kingdom and the early years of the New Kingdom. When the power of the Pharaoh was diminished, however, the priesthood tended to become more powerful; such as in the latter years of the New Kingdom and during the Third Intermediate Period.

The Battle of Djahy was a defensive battle fought by the Egyptians against a nomadic confederation of raiders known as the Sea People, who invaded Egypt consistently over many years during the Third Intermediate Period.

The Twenty-Fifth Dynasty of Egypt was the last ruling dynasty of the Third Intermediate Period. The dynasty had the misfortune of coexisting with the rising power of Assyria and was dealt a devastating blow when Assyrian forces sacked the cities of Thebes and Memphis in the seventh century BCE.

During the seventh century BCE, the power of the Egyptian empire had waned substantially. The territory had been ruled by foreign invaders (from Libya and Nubia) for several generations and the state was greatly weakened by internal conflict and decentralization of power. The rising Assyrian Empire, which emerged in the Middle East, took advantage of this situation and conquered most of Egypt in the seventh century.

The Sack of Jerusalem took place during the tenth century BCE. It is generally believed that the Egyptian forces were led by one of the Libyan rulers of Egypt, most likely Shoshenq I. Although, there is a considerate amount of disagreement among historians and Egyptologists owing to the paucity of reliable historical evidence from this time period. 

We know the most about the Sea Peoples from Egyptian accounts such as the Great Karnak Inscription of Merneptah, although similar phenomena are described in Levantine, Anatolian and Mesopotamian sources, suggesting a massive marine migration of loosely affiliated peoples who disrupted the stability of the entire region. These migrations and invasions were an essential, although not the only, element in what is described as the Bronze Age Collapse. Rather than the powerful empires consolidating their strength and spheres of influences, instead this resulted in the destruction of long-standing states (the Hittite Empire and Mycenaean Greece), as well as the immense weakening of Egypt during its transition from the New Kingdom to the Third Intermediate Period. Egypt eventually weakened to the point that it became susceptible to conquest by the Assyrians, and then in turn the Babylonians, Persians, Greeks and Romans. While the Sea Peoples are sometimes blamed from the collapse of Mycenaean civilization, an alternative postulation is that the Sea Peoples themselves consisted of native Greeks displaced by political and environmental factors, forcing them to travel by sea to populate and invade Egypt and the Levant. This is supported by linguistic and archaeological evidence of the Philistines, who appear to have spoken an Indo-European language related to Greek, and whose art and pottery strongly resembles earlier Greek forms. 

King Kashta of Kush invaded Egypt during the 8th Century BCE, conquering the country. The emperors of Kush then ruled as pharaohs of Egypt for the 25th dynasty, until they were removed by the Assyrians. 

The Battle of Megiddo was fought in 609 BCE. It was part of a larger conflict between the declining Assyrian Empire and the ascending Neo-Babylonian Empire. The Egyptians were led by Necho II, an Assyrian puppet ruler. The Battle of Megiddo was fought between Egypt and the Kingdom of Judah (a would-be ally of the Neo-Babylonians). It ended in victory for the forces of Egypt and Necho II, which captured Judah and joined up with the Assyrian army at Carchemish. It proved to be a pyrrhic victory, however, as the combined Egyptian and Assyrian army was promptly destroyed by the forces of Nebuchadnezzar II and the Neo-Babylonian Empire.

The Battle of Carchemish was fought in 605 BCE. It was contended by an alliance of Assyria and Egypt and an alliance of Babylon and Persia. It ended in the complete destruction of the Egyptian army, the downfall of the Assyrian Empire, and the ascendancy of the Neo-Babylonian Empire.