Egyptian Libyan Twenty-third Dynasty of Osorkon III – Takelot III – Rudamun, but this kingdom quickly fragmented after Rudamun's death, with the rise of local city states under kings such as Peftjaubast of Herakleopolis, Nimlot of Hermopolis, and Ini at Thebes. Twenty-fourth Dynasty The Nubian kingdom to the south took full advantage of this division and the ensuing political instability. Prior to Piye's Year 20 campaign into Egypt, the previous Nubian ruler – Kashta – had already extended his kingdom's influence into Thebes when he compelled Shepenupet, the serving Divine Adoratice of Amun and Takelot III's sister, to adopt his own daughter Amenirdis, to be her successor. Then, 20 years later, around 732 BC his successor, Piye, marched north and defeated the combined might of several native Egyptian rulers: Peftjaubast, Osorkon IV of Tanis, Iuput II of Leontopolis and Tefnakht of Sais. Twenty-fifth Dynasty Piye established the Twenty-fifth Dynasty and appointed the defeated rulers as his provincial governors. He was succeeded first by his brother, Shabaka, and then by his two sons Shebitku and Taharqa. The reunited Nile valley empire of the 25th Dynasty was as large as it had been since the New Kingdom. Pharaohs of the dynasty, among them Taharqa, built or restored temples and monuments throughout the Nile valley, including at Memphis, Karnak, Kawa, and Jebel Barkal. The 25th Dynasty ended with its rulers retreating to their spiritual homeland at Napata. It was there (at El-Kurru and Nuri) that all 25th Dynasty pharaohs were buried under the first pyramids to be constructed in the Nile valley in hundreds of years. The Napatan dynasty led to the Kingdom of Kush, which flourished in Napata and Meroe until at least the 2nd century AD. The international prestige of Egypt had declined considerably by this time. The country's international allies had fallen firmly into the sphere of influence of Assyria and from about 700 BC the question became when, not if, there would be war between the two states as Esarhaddon had realised that a conquest of Lower Egypt was necessary to protect Assyrian interests in the Levant. Despite Egypt's size and wealth, Assyria had a greater supply of timber, while Egypt had a chronic shortage, allowing Assyria to produce more charcoal needed for iron-smelting and thus giving Assyria a greater supply of iron weaponry. This disparity became critical during the Assyrian invasions of Egypt over the period 670–663 BC.