Ramesses I, who had been general and vizier under Horemheb (18th Dynasty), succeeded to the throne at an advanced age and only ruled for a short period. He was succeeded by his son, Sethos I. The name of this king indicates that this god became increasingly popular in this period. Sethos I conducted various campaigns against tribes moving into Palestine and against Libya. Among Sethos I's construction works are the great hypostyle hall in the temple of Karnak and a temple and cenotaph in Abydos. Sethos I's tomb is the largest in the Valley of the Kings. Sethos I was succeeded by Ramesses II. This king, who reigned for 67 years, eventually signed a peace treaty with the Hittites after a period of war (including the Battle of Kadesh). Many important buildings were erected during his reign, including the temples of Abu Simbel. Under Merenptah, Egypt was faced with attacks by Libyans and various peoples from western Asia (the so-called Sea Peoples), who were defeated in the Delta, but nevertheless continued to penetrate Egypt. The period after Merenptah was characterised by struggles for the throne. Various kings ruled for short or long periods: Sethos II, Amenmesse, Siptah and Tawosret. In the meantime, the High Priests of Amun grew ever more powerful.