Patrick de Dunbar, 9th Earl of Dunbar and/or 2nd Earl of March (1285-1369) was a Scottish noble prominent during the reigns of the Bruce kings, Robert I and David II. The earldom, located in Lothian, and known interchangeably by names Dunbar and March (so-called Northumbrian or Scottish March), was one of successor fiefs of Northumbria, an Anglo-Saxon Kingdom and later Earldom. The Dunbar family descended from one branch of ancient Earls of Northumbria, specifically from a branch which also had Scottish royal blood. His father, the 8th Earl of Dunbar, who had obtained the recognition for the title Earl of March (thus being counted as the 1st Earl of March), was Edward I of England's lieutenant in Scotland, but also held a claim to the crown of Scotland, made in 1291, by his wife, Marjory, daughter of Alexander Comyn, earl of Buchan, and/or by being descended from King Donald III Bane.

The name 'Dunbar', was derived from the family castle and estate, and became an hereditary surname with its adoption as a name by the 4th Earl.

After the Battle of Bannockburn, Patrick Dunbar gave sanctuary and quarter to the English King Edward II at the fortress of Dunbar Castle , on the east coast of Scotland between Edinburgh and Berwick, and managed to effect the king's escape by means of a fishing boat whereby the wayward monarch was transported back to England, against all that might be considered sacrosanct by the suffering Scots. His intentions remain unclear. In 1333, frustrated by English interests in his inheritance of the great castle, Dunbar had the original castle levelled to the ground. Later, Edward III of England compelled him to rebuild the fortress at his own expense, and, with a total disregard to the circumstance of his imposition upon the royal house of Scotland, not an unusual imposition by that tradition of English royalty, used it to barrack English troops. After four years, in 1338, the castle was returned to Patrick's possession to command. Patrick Dunbar, governor of Berwick Castle (title bestowed by Robert the Bruce) commanded the Scottish army at the fateful Battle of Durham in October 1346. "He escaped with considerable losses."

Patrick Dunbar is not as well remembered as his wife Agnes Dunbar, 4th Countess of Moray, also known as Black Agnes of Dunbar. He died just a few months after his wife.