The Kingdom of Kush or Kush (/kʊʃ, kʌʃ/) was an ancient Nubian kingdom situated on the confluences of the Blue Nile, White Nile and River Atbara in what is now the Republic of Sudan. The Kushite era of rule in Nubia was established after the Bronze Age collapse and the disintegration of the New Kingdom of Egypt, and it was centered at Napata in its early phase. After King Kashta ("the Kushite") invaded Egypt in the 8th century BC, the Kushite emperors ruled as pharaohs of the Twenty-fifth dynasty of Egypt for a century, until they were expelled by the Assyrians under the rule of Esarhaddon.