Lord Blantyre was a title in the Peerage of Scotland. It was created in 1606 for the politician Walter Stewart. The lordship was named for Blantyre Priory in Lanarkshire, where Walter Stewart had been commendator. The main residences associated with the Lords Blantyre were Erskine House (Renfrewshire), Lennoxlove House (East Lothian) and Place of Cardonald (Renfrewshire).

Walter Stewart, 1st Lord Blantyre was educated with James VI under George Buchanan at Stirling Castle, he was a gentleman in the king's chamber, Knight of Cardonald, Prior of Blantyre, Keeper of the Privy Seal of Scotland from 1582 to 1596, an Extraordinary Lord of Session from 1593, an Octavian from 1596, and Lord High Treasurer of Scotland from 1596 to 1599.

Between 1587 and 1593 Walter Stewart held the barony of Glasgow, in place of the young Duke of Lennox, and so he appointed the magistrates and Provost of Glasgow. James VI sent John Carmichael and Blantyre to arrest Elizabeth's Irish rebel Brian O'Rourke and take him to England on 3 April 1591. This caused a riot in Glasgow, because the arrest was thought likely to damage the Irish trade, and Blantyre and Carmichael were cursed as "Queen Elizabeth's knights" and the king for taking "English angels", the annuity or subsidy received from Queen Elizabeth.

Blantyre fell off his horse and broke his leg in Edinburgh in February 1597, and while he recovered Lord Ochiltree was treasurer. In 1599 he was imprisoned and compelled to resign by James VI, influenced by a group of courtiers in king's bedchamber.

In July 1602 Blantyre joined a committee of "4 Stewarts" to arbitrate between the Marquess of Huntly and the Earl of Moray. The other Stewarts were Lord Ochiltree, Alexander Stewart of Garlies, and the Tutor of Rosyth.

He was a commissioner for union with England in 1604. He was created Lord Blantyre, in the Peerage of Scotland in 1606, and succeeded by William Stewart.

Upon the death of the 12th Lord Blantyre in 1900 the title became extinct, with the Blantyre estates passing to his grandson, William Arthur Baird.