King Olaf III of Norway (Norwegian spelling Kyrre Olav III). He reigned as King from 1067 to 1093, with the first two years jointly with his brother, Magnus II. He was born in Norway, the youngest son of King Harald III "Hardrada" Sigurdsson and his queen, Tora Torbergsdatter. At the age of 16, he joined his father for his ill-fated invasion of England in 1066. He did not participate in the Battle of Stamford Bridge on September 25, 1066, where his father was defeated and killed by the Saxon King Harald Godwinson, but remained on a ship with his father's reserve forces. He returned to the Orkney Islands with his father's remains and stayed there during the winter of 1066-1067, returning to Norway in the summer of 1067. His father had declared his older brother, Magnus, regent king prior to leaving for England. When Olaf arrived in Norway, he asked Magnus (now Magnus II) for his share of the kingdom under Norwegian property laws. Magnus agreed, giving him the northern half of Norway while retaining the southern half. When Magnus II died on April 28, 1069, Olaf became the sole ruler of Norway as Olaf III or Olaf Kyrre. Under his rule, Norway experienced a rare extended period of peace in where he sought to avoid conflict by way of agreements and establishing marriage connections. He focused efforts on rebuilding the Church's organizational structure and modernizing the country. When Danish King Svend Estridsen considered attacking Norway because he felt no longer bound by the ceasefire agreement between him and Harald III that was signed in 1064, Olaf made peace by marrying his daughter, Ingerid Svendsdatter. Additionally, he made peace between Norway and the new English king William the Conqueror. Unlike his father, Olaf accepted the authority of the Church in Norway and allowed the bishops to establish residences in Oslo, Bergen, and Nidaros, rather than being a permanent part of the king's court and travelling with the king to conduct ecclesiastical affairs. He directed the construction of churches, including Christ Church in Bergen and the Nidaros Cathedral in Trondheim. He also strengthened the power of the king and instituted the system of guilds, as well as writing secure provincial laws, including the Norwegian law Gulatingsloven. In the autumn of 1093 he became ill and died in Hakeby, located in the present-day Vastra Gotaland County in western Sweden. He had no children with his wife; however, he had a son with his mistress, Tora Arnesdatter, who later became King Magnus III Olafsson. In 1992 a memorial to King Olaf III Kyrre was erected in Bergen, Norway, to commemorate the city's 900th year anniversary.