Answer:
The factors leading to the decline of ancient Egypt were largely uncontrollable. A civil war coupled with invasions by the Assyrians weakened the Egyptian military allowing the Persian empire to successfully invade and take over Egypt.
Ancient Egypt went through a series of occupations and suffered a slow decline over a long period of time. First occupied by the Assyrians, then the Persians, and later the Macedonians and Romans, Egyptians would never again reach the glorious heights of self-rule they achieved during previous periods.
Explanation:
While the Empire's wealth, power and military might wax and waned, it largely retained its independence until a combination of climate change, economic, political and military factors led to its eventual decline, fragmentation and fall.
In the waning years of the Empire, Egypt fell to the Sasanian Persian army in the Sasanian conquest of Egypt (618–628). It was then recaptured by the Roman Emperor Heraclius (629–639), and was finally captured by Muslim Rashidun army in 639–641, ending Roman rule.
