Middle Kingdom of Egypt arose when Mentuhotep II of Eleventh Dynasty unified Egypt once again between 2041 and 2016 BC beginning with his conquering of Tenth Dynasty in 2041 BC. Pyramid building resumed, long-distance trade re-emerged, and the center of power moved from Memphis to Thebes. Connections with the southern regions of Kush, Wawat and Irthet at the second cataract were made stronger. Then came the Second Intermediate Period, with the invasion of the Hyksos on horse-drawn chariots and utilizing bronze weapons, a technology heretofore unseen in Egypt. Horse-drawn chariots soon spread to the west in the inhabitable Sahara and North Africa. The Hyksos failed to hold on to their Egyptian territories and were absorbed by Egyptian society. This eventually led to one of Egypt's most powerful phases, the New Kingdom (1,580–1,080 BC), with the Eighteenth Dynasty. Egypt became a superpower controlling Nubia and Judea while exerting political influence on the Libyans to the West and on the Mediterranean.