Isabella of Mar was a Scottish noblewoman born around 1320. She was the daughter of Donald, Earl of Mar and Isabella of Scotland. Isabella became notable for her marriage to Robert the Bruce, the King of Scotland, which strengthened political alliances during a tumultuous period in Scottish history. After the death of her husband, Isabella played a significant role in the governance of the Earldom of Mar. She was known for her intelligence and leadership, managing her estates and supporting the Scottish cause during the Wars of Scottish Independence. Isabella's legacy is remembered as part of Scotland's rich medieval history.