Which ancient civilization defeated the ancient Egyptian civilization?

A few Civilizations defeated the Egyptians, resulting in what are know as Intermediary periods. The Nubians, The Hyksos Kings (Isrealites), The Persian Empire all ruled in Egypt for short periods.

Alexander the Great, actually liberated the Egyptians from the Persian Empire, who ruled in Egypt for around 200 years.

The Persians where probably the true defeaters of the Egyptian civilization, because that would be the last time Egypt would be ruled by native Egyptians, Egypt would be ruled by Greeks for the next 300 Years.

The Romans conquered Egypt in about 30 BC, when Octavian defeated Mark Anthony and Annexed Egypt to the Roman Empire, and this is generally considered to be the end of the rule of the pharaoh's..

>>Greek or Macedonian, Alexander the Great in any case.