Mary of Scotland (1082–1116) was the younger daughter of Malcolm III of Scotland and his second wife Margaret of Wessex. Mary was a member of the House of Dunkeld by birth, and was Countess of Boulogne by marriage.
Mary was the youngest of eight children. Her brothers included: Edmund, Ethelred, Edgar, King of Alba, Alexander I of Scotland and David I of Scotland. Mary had only one sister, Matilda of Scotland, first wife of Henry I of England. Mary was a maternal aunt of Empress Matilda, who pressed her claim on the Kingdom of England but lost out to her cousin, Stephen. Stephen was married to Matilda, Mary's daughter.
When Mary was about four years old, in 1086, she and her sister, Matilda, were sent by their parents to Romsey. Their maternal aunt, Christina, was abbess there.
The two girls spent their early life at the monastery with their aunt, where they also received part of their education. Some time before 1093, they went to Wilton Abbey, which also had a reputation as a centre of learning, to finish their education. One of its inhabitants was the poet Muriel, who attracted much attention from scholars throughout Europe. Matilda received many proposals for marriage but refused them all for the time being.
Matilda finally left the monastery in 1100 to marry King Henry I of England. At first the marriage was unacceptable, as Matilda and Mary had both spent their childhood in the abbey and were both considered to be nuns. Henry did however get permission to marry Matilda.
Mary herself left the abbey in 1096. Matilda wanted her to also marry, so Henry I married her off to Eustace III, Count of Boulogne, son of Eustace II of Boulogne and his wife, Ida of Lorraine. The marriage lasted for twenty years but only produced a daughter:
- Matilda of Boulogne (1105–1152), became countess of Boulogne after the death of her father. Married Stephen of England, hence she became Queen of England. They were parents of Eustace IV, Count of Boulogne, William of Blois and Marie of Boulogne.
Mary died in 1116, nine years before her husband died. The same year of Eustace III's death, Matilda married Stephen.
The daughters of Matilda and Mary of Scotland, both called Matilda, fought each other for control of England. Matilda of Boulogne raised an army after Matilda of the English had captured Stephen. Matilda of Boulogne won in the end. Stephen was released and was once again proclaimed King of England.
When Stephen died, he was forced to bequeath the English crown to his first cousin once removed, Matilda of the English's son Henry. On Stephen's death, it seemed that Matilda of Scotland's daughter, Matilda, had won because her son and his descendants sat on the throne.