Christian (or Christina) de Brus (c. 1278 – 1356/1357) was a sister of Robert the Bruce, King of Scots. It is presumed that she and her siblings were born at Turnberry Castle in Carrick to Marjorie, Countess of Carrick, and her husband, Robert de Brus, jure uxoris Earl of Carrick. Christina is thought to have married Gartnait, son of Donald, Earl of Mar (died 1305), but recently scholars have debated the truth of the claim, because Christina is never described as a countess of Mar, or even described as 'of Mar.'
Her first marriage was to Sir Christopher Seton, who was born in 1278 and executed in 1306. She remarried in 1326 to Sir Andrew Murray, the posthumous child in 1298 of Sir Andrew Murray, a joint victor of the battle of Stirling Bridge along with William Wallace. Sir Andrew died in 1338.
Along with King Robert I's other female relatives, she was captured shortly after his rebellion. Christina was sent to a convent at Sixhills in Lincolnshire, England., while her sister Mary and Bruce's supporter Isabella MacDuff, Countess of Buchan, were imprisoned in cages.
In 1335, during the Second War of Scottish Independence, she commanded the garrison of Kildrummy Castle and successfully held out against pro-Baliol forces led by David of Strathbogie, prior to their defeat by her husband, Sir Andrew Murray, at the Battle of Culblean.
- Peter Traquair "Freedom's Sword"
- Fiona Watson, "Bruce, Christian (d. 1356)", Oxford Dictionary of National Biography, Oxford University Press, 2004