Isabella of Mar (fl. c. 1277 – 12 December 1296) was the first wife of Robert Bruce VII, Earl of Carrick. Isabella died before her husband was crowned (as Robert I) King of Scotland. She and her husband were the grandparents of Robert II, King of Scotland, founder of the Royal House of Stuart.
Isabella was the daughter of Domhnall I, Earl of Mar (died 1297 - 1302) and Elena, daughter of Llywelyn the Great (died after 1295). Isabella's father was evidently an adherent of Robert Bruce V, Lord of Annandale (died 1295), a man who staked a claim to the Scottish throne. The close relationship between Domhnall's family and the Bruces
is evidenced by two marriages; the first between Isabella and Robert,
and the second between Domhnall's son and comital successor, Gartnait (died c.1302), and a sister of Robert Bruce VII.
The marriage of Robert Bruce VII and Isabella probably took place in the 1290s. The union produced a single child, a daughter named Marjorie (died 1316), who was born in about 1296. Robert and Isabella's daughter, Marjorie, married Walter Stewart, Steward of Scotland, and their son eventually reigned as Robert II, King of Scotland (died 1390).
Six years after Isabella's death in childbirth, Robert Bruce VII married his second wife, Elizabeth de Burgh (died 1327).
As the daughter of an Earl, Isabella's life was deeply entwined with the
politics of her kingdom. In 1286, a few years after her birth, King Alexander III was found dead on the shores near Kinghorn. His heir, Margaret of Norway, was too young to take the throne at this time, but four years later in 1290, she was brought to Orkney, where she died at 7 years old. What followed was Scotland's most notorious succession dispute, one that eventually led to Bruce's ascension and the Scottish Wars of Independence. After Margaret's death, the Scottish nobles formed factions in support of the two primary families vying for the throne, the House of Balliol and the House of Bruce. The fate of Isabella, her kingdom, and the future Stewart dynasty all hinged on these two houses.
At around the same time, Isabella's father, Domhnall I, Earl of Mar, was seeking a strong ally that could protect his clan from covetous neighbors. When the succession crisis first arose, Domhnall was already amid a clan dispute with John Comyn of Badenoch. Domhnall claimed that the Comyns
had pillaged his lands, and he was thus eager for an excuse to take up
arms against this powerful neighbor. As the Comyns were staunch
supporters of John Balliol’s claim to the throne, Domhnall found a natural ally in Clan Bruce. As the chronicler, John of Fordun, wrote “all the Comyns and their whole abettors stood by Balliol; but the earls of Mar and Atholl, with the whole strength of their power, cleaved, in the firm league of kinship, to the side of Robert of Bruce.”
Domhnall summoned an army within a mere fortnight of Margret's death,
eager and ready to support his newfound ally. This succession dispute,
or “Great Cause,” was what initially brought Isabella's Clan Mar and the
House of Bruce together as allies.
Isabella's father sought to use Isabella to strengthen ties with
the powerful Bruce family. And though Clan Mar had no shortage of
enemies prior to Margret's death, the succession dispute and their
siding with Bruce had brought them new opponents. There was thus a great
pressure on the part of Domhnall to sow a strong bond with new allies
who could protect the Mars from their growing list of enemies, and in
this age of diplomatic marriage, that meant that Isabella was to wed into an allied clan. The premier choice for Isabella's spouse was the young Robert the Bruce, the Earl of Carrick and future King of Scots—and also the grandson of Robert de Brus, 5th Lord of Annandale,
who was vying for the throne at that time. In the late thirteenth
century, the 5th Lord of Annandale was nearing the end of his life, and
thus, Domhnall saw the young Earl of Carrick as a potential future king.
By pursuing a marriage between Isabella and Bruce, Domnall was not only
strengthening his bond with allies, which was his primary goal but was
also marrying into a powerful family that might one day rule the
kingdom. Isabella, like many European noblewomen in the medieval age,
was used as a diplomatic pawn by her ambitious father.
The House of Bruce's interest in Isabella was politically motivated as
well, though their interest existed before the succession dispute. To
the North of the Earldom of Mar laid the lordship of Garioch. Garioch was a land divided between four different co-heirs, including the House of Bruce. Two of the other co-heirs were John Balliol and John Hastings,
who would later fight Bruce for the throne. In April 1290, Bruce made
an agreement with Nichlas Biggar, a minor nobleman who held a legal
claim to Garioch. This arrangement granted Bruce the two-thirds of the
lordship which Balliol and Hastings held; yet, in the end, the
arrangement was insubstantial for attaining the lordship, so Bruce
turned his eyes south to Clan Mar. As historian Michael Brown wrote:
As Earl Donald's [Domnall’s] earldom bordered the Garioch and since he held lands in the lordship as Balliol's vassal,
Donald had a direct interest in the process. These overlapping landed
concerns may have fuelled the growing political alignment between Mar
and Bruce which was, once again, formalised through marriage.
Even
before the succession dispute, the House of Bruce sought a marriage
with Clan Mar to strengthen their claim on the lordship of Garioch.
Their interests would only “overlap” further with Margret's death and
Balliol's rival claim. The marriage between Isabella and Bruce was thus
politically motivated—the two clans shared enemies and sought to
strengthen their political ties through the marriage. Wikipedia