In his twentieth regnal year, Amenemhat established his son Senusret I as his coregent,[1] beginning a practice which would be used repeatedly throughout the rest of the Middle Kingdom and again during the New Kingdom. In Amenemhet's thirtieth regnal year, he was presumably murdered in a palace conspiracy. Senusret, campaigning against Libyan invaders, rushed home to Itjtawy to prevent a takeover of the government.[23] During his reign, Senusret continued the practice of directly appointing nomarchs,[24] and undercut the autonomy of local priesthoods by building at cult centers throughout Egypt.[25] Under his rule, Egyptian armies pushed south into Nubia as far as the Second Cataract, building a border fort at Buhen and incorporating all of Lower Nubia as an Egyptian colony.[26] To the west, he consolidated his power over the Oases, and extended commercial contacts into Syrio-Palestine as far as Ugarit.[27] In his 43rd regnal year, Senusret appointed Amenemhet II as junior coregent, before dying in his 46th.[28]