Robert Sempill, 3rd Lord Sempill (c. 1505–1576) was a Scottish lord of Parliament.
Robert, also Semphill or Semple, 3rd Lord Sempill (d. circa 1575), commonly called the 'Great Lord Sempill', was the elder son of William Sempill, 2nd Lord Sempill, by his first wife, Lady Margaret Montgomery, eldest daughter of Hugh Montgomerie, 1st Earl of Eglinton. His parents' marriage was commemorated in carved stone heraldry at Castle Semple Collegiate Church. Through her paternal grandmother, Lady Margaret Montgomery was a fifth generation descendant from Robert II of Scotland. So descendants of Robert, 3rd Lord Sempill, are descended from many Scottish monarchs up to Robert II, and also from Anglo-Saxon kings (through the marriage of Malcolm III of Scotland to Saint Margaret of Scotland).[1]
The Sempill family from the thirteenth century were hereditary bailiffs of the regality of Paisley and sheriffs of Renfrew under the Lord High Steward of Scotland. They frequently distinguished themselves in the English wars, and were employed in important duties of state. Sir Thomas Sempill, father of John Sempill, 1st Lord Sempill, was killed at the battle of Sauchieburn on 11 June 1488, fighting in support of James III, and the first Lord Sempill, created by James IV about 1489, fell at Flodden on 9 September 1513.