Robert II (March 2, 1316 – April 19, 1390), king of Scots, called "the Steward", a title that gave the name to the House of Stewart (or Stuart). He ruled from 1371 until his death.

Robert was the sole son of Walter Stewart, 6th High Steward of Scotland (d. 1326) and Marjorie Bruce, daughter of King Robert I of Scotland and his first wife Isabella of Mar. He was delivered by caesarean section. His mother survived his birth by some hours at most.

In 1318 the Scottish parliament decreed that if King Robert died without sons the crown should pass to his grandson; but the birth of a son afterwards, King David II, to Bruce in 1324 postponed the accession of Robert for nearly forty-two years. Soon after the infant David became king in 1329, the Steward began to take a prominent part in the affairs of Scotland. He was one of the leaders of the Scottish army at the battle of Halidon Hill in July 1333; and after gaining some successes over the adherents of Edward Balliol in the west of Scotland, he and John Randolph, 3rd Earl of Moray (d. 1346), were chosen as regents of the kingdom, while David sought safety in France.

The colleagues soon quarrelled; then Randolph fell into the hands of the English and Robert became sole regent, meeting with such success in his efforts to restore the royal authority that the king was able to return to Scotland in 1341. Having handed over the duties of government to David, the Steward escaped from the battle of Neville's Cross in 1346, and was again chosen regent while the king was a captive in England. Soon after this event some friction arose between Robert and his royal uncle. Accused, probably without truth, of desertion at Neville's Cross, the Steward as heir-presumptive was greatly chagrined by the king's proposal to make Edward III of England, or one of his sons, the heir to the Scottish throne, and also by David's marriage with Margaret Logie.

In 1363 he rose in rebellion, and after having made his submission was seized and imprisoned together with four of his sons, being only released a short time before David's death in February 1371. By the terms of the decree of 1318 Robert now succeeded to the throne, and was crowned at Scone, Perthshire in March 1371. He was not a particularly active king. Some steps were taken by the nobles to control the royal authority. In 1378 a war broke out with England; but the king took no part in the fighting, which included the burning of Edinburgh and the Scottish victory at the Battle of Otterburn in 1388.

As age and infirmity were telling upon him, the estates in 1389 appointed his second surviving son Robert, Earl of Fife, afterwards Duke of Albany, guardian of the kingdom. The king died at Dundonald in 1390, and was buried at Scone.

His first wife was Elizabeth, daughter of Sir Adam Mure of Rowallan, a lady who had formerly been his mistress. Robert had married her in 1336, but as the marriage had been criticised as uncanonical, he remarried her in 1349. By her he had at least ten children:
• John Stewart (d. 1406), later king as Robert III
• Alexander of Buchan (1343–1394)
• Margaret Stewart, married John MacDonald, Lord of the Isles
• Walter Stewart (d. 1362), married Isabel Macduff, 9th Countess of Fife
• Robert of Albany (1339–1420)
• Marjory Stewart, married first John Dunbar, 5th Earl of Moray, second Alexander Keith
• Jean Stewart, married in 1373 Sir John Keith, in 1379 Sir John Lyon, in 1384 Sir James Sandilands
• Isabel Stewart, married first James Douglas, 2nd Earl of Douglas, married second David Edmondstone
• Katherine Stewart
• Elizabeth Stewart, married Sir Thomas Hay, Lord High Constable of Scotland

By his second wife, Euphemia, daughter of Hugh de Ross, 4th Earl of Ross, and widow of the 3rd Earl of Moray, formerly his colleague as regent, he had five children:
• David Stewart, 1st Earl of Caithness (d. bef. 1389)
• Walter Stewart, 1st Earl of Atholl (d. 1437)
• Margaret Stewart
• Elizabeth Stewart, married 1380 David Lindsay, 1st Earl of Crawford
• Egidia Stewart, married 1387 Sir William Douglas of Nithsdale

The confusion about the circumstances of his first marriage would later lead to conflict amongst the descendants of his first marriage (which included James I of Scotland) and the unquestionably legitimate descendants of his second marriage.

Robert had also eight illegitimate children, mostly by unknown mothers.