Fergus of Galloway married to David's older sister, Edith (died 1118), a union which closely bound him to the Scottish royal house. For as long as Henry I lived, relations between him and David remained harmonious. When the former died in 1135, however, the peace between the neighbouring realms was shattered when his nephew, Stephen of Blois, Count of Boulogne and Mortain (died 1154), successfully seized the throne. Before the end of the year, the Scots surged forth and seized Carlisle and Cumberland before peace was restored. Relations broke down the following year, and the Scots again invaded in 1137, seizing Northumberland, and
Henry I of Werle Henry I of Werle Henry I (died 8 October 1291) was a Prince of Mecklenburg-Werle and Mecklenburg-Güstrow. He was the son Prince Nicholas I of Mecklenburg-Werle and his wife Princess Jutta of Anhalt the daughter of Prince Henry I of Anhalt and his wife Princess Irmgard of Thuringia. Henry and his brother John ruled Mecklenburg-Werle jointly following the death of their father on 10 May 1277. Henry and his brother ruled jointly until 1283 when Henry founded the principality of Mecklenburg-Güstrow while John took up residence in the principality of Mecklenburg-Parchim which he ruled jointly with Prince Pribislaw II. Henry's