 George Munro, 1st of Culrain was the third son of George Munro, 1st of Newmore who himself was a royalist soldier of the 17th-century and a cadet of the Munro of Obsdale family.The estate of Culrain was apparently named after Coleraine in Ireland of which George Munro, 1st of Newmore had been the governor.The Newmore estate had passed to the elder half-brother of George Munro, 1st of Culrain.