The Third Intermediate Period of Egypt lasted about 400 years , commonly dated from c. 1070 BCE to 664 BCE. Some sources use slightly different start and end dates, but that gives the usual span.

Quick scoop

  • Main estimate: about 406 years if you count from 1070 to 664 BCE.
  • Broader date ranges: some references extend it a bit differently, which is why you may also see 1069–525 BCE in some summaries.
  • Most standard classroom/history use: 1070–664 BCE.

Why the dates vary

Egyptian period boundaries are not always exact because political control changed gradually rather than on one single day. Different historians may mark the start or end by different dynastic shifts or foreign conquests.

TL;DR

The Third Intermediate Period in Egypt lasted roughly four centuries.