During the second period or the Old Kingdom, which lasted from 2686 to 2181 BC, there were many advances in architecture, art, and technology. The Pyramids and Sphinx are thought to have been created during this time. This period was a golden age of peace. Over the course of the fifth and sixth dynasties, the kingdom's wealth started to fall. It was not until the death of the sixth dynasty's king, King Pepy II, that the Old Kingdom ended and all of Egypt fell into chaos.
After the collapse of the Old Kingdom, the third period or First Intermediate Period, which lasted from 2181 to 2055 BC, saw success with the seventh and eight dynasties. It was not until 2160 BC where central authority fell, causing War between governors. During this era of conflict two different kingdoms arose: A line of 17 rulers (dynasties nine and 10) ruled Middle Egypt between Memphis and Thebes, while another family of rulers arose in Thebes to challenge central power. Around 2055 BC, the Theban prince Mentuhotep managed to topple Middle Egypt, and reunited Egypt.