Isabella mac William (born 1165) (Gaelic: ''Isibéal nic Uilliam'') was the illegitimate daughter of

William the Lion William the Lion, sometimes styled William I and also known by the nickname Garbh, "the Rough"''Uilleam Garbh''; e.g. Annals of Ulster, s.a. 1214.6; Annals of Loch Cé, s.a. 1213.10. ( 1142 – 4 December 1214), reigned as King of Scots from 11 ...

King of Scots The monarch of Scotland was the head of state of the Kingdom of Scotland. According to tradition, the first King of Scots was Kenneth I MacAlpin (), who founded the sovereign state, state in 843. Historically, the Kingdom of Scotland is thoug ...

by a daughter of

Robert Avenel Robert Avenel (died 8 March 1185) was a 12th-century Anglo-Norman magnate. He was ruler of the small former Northumbrian province of Eskdale in Dumfriesshire, as well as Abercorn in West Lothian. He was one of a small number of Anglo-Norman immi ...

. She married

Robert III de Brus Robert II de Brus, ''le Meschin (the Cadet)'' ( fl. 1138, died ) was a 12th-century Norman noble and 2nd Lord of Annandale. He was the son, perhaps the second son, of Robert de Brus, 1st Lord of Annandale. The elder de Brus' allegiances were comp ...

in 1183. They had no children. After his death in 1191, Isabella was married to Robert de Ros, Baron Ros of Wark (died 1227). They had the following children: * Sir William de Ros (b. before 1200 – d. ca. 1264/1265). * Sir Robert de Ros (ca. 1223 – 13 May 1285), was Chief Justice of the Kings Bench. He married Christian Bertram. * Sir Alexander de Ros (d. ca. 1306), who fathered one child, William, with an unknown wife. * Peter de Ros.

References

{{DEFAULTSORT:Isabella Mac William 1160s births Year of death unknown 12th-century Scottish people 12th-century Scottish women Illegitimate children of Scottish monarchs De Ros family House of Dunkeld House of Bruce Daughters of kings