Robert Baillie, a Scottish theologian, born at Glasgow in 1599, died in July, 1662. He was educated at the Glasgow university and ordained by Archbishop Law in 1622. In the religious controversies of the day he generally preserved a moderate tone. He was a member of the general assembly of 1638, which protested against the episcopacy, and in 1640 was chosen as commissioner to London to prefer charges against Archbishop Laud. On his return to Glasgow in 1642 he became a professor of divinity in the university, and in the following year he was sent as a delegate to the Westminster assembly of divines, where he maintained the rights of the presbytery with great spirit. After the execution of Charles I. in 1649 he was sent to Holland to invite Charles II. to accept the crown and covenant of Scotland. After the restoration in 1660 he was made principal of the Glasgow university. Dr. Baillie wrote Opus Historicum et Chronologi-cum (Amsterdam, 1663) and many other works, mostly theological pamphlets and discussions.

His "Letters and Journals," of great historical value, were first published in 1775, at the instance of Hume and Robertson (new ed., 3 vols. 8vo, 1841-'3).