The Battle of Grathe Heath was fought in 1157 between the Danish armies of Valdemar I and his rival Sweyn III. Valdemar's forces won the battle, and Sweyn III was slain while attempting to flee. Events Births September 8 - King Richard I of England (died 1199) Leopold V of Austria (died 1194) Hojo Masako, wife of Minamoto no Yoritomo (died 1225) Deaths August 21 - King Alfonso VII of Castile (born 1105) Agnes of Babenberg, daughter of Leopold III of Austria Sweyn III of Denmark Yury... Casus belli is a Latin expression from the international law theory of Jus ad bellum. ... Valdemar I the Great (1131-1182) was King of Denmark from 1157 until 1182. ... Sven III Grathe (11XX - 1157) was the king of Denmark between 1146 and 1157. ... Events Births September 8 - King Richard I of England (died 1199) Leopold V of Austria (died 1194) Hojo Masako, wife of Minamoto no Yoritomo (died 1225) Deaths August 21 - King Alfonso VII of Castile (born 1105) Agnes of Babenberg, daughter of Leopold III of Austria Sweyn III of Denmark Yury... Valdemar I the Great (1131-1182) was King of Denmark from 1157 until 1182. ... Sven III Grathe (11XX - 1157) was the king of Denmark between 1146 and 1157. ...