In 1715 John Greg, a descendant of the McGregor clan, sailed from the family home in Ayrshire to seek his fortune in Ulster. He soon built a successful business as a merchant, his own sons becoming successful businessmen. Half a century later two of his grandsons, Thomas and Samuel, sailed back to Britain and founded businesses of their own at opposite ends of England, Thomas in banking and finance, Samuel in textiles. Helped by the patronage and finance of Robert Hyde, Samuel became a prominent figure in the development of the cloth industry. He helped to take the industry forward by investing heavily in the adoption of water power, and founded Quarry Bank Mill in north Cheshire, which today is open to visitors as a National Trust property. Meanwhile brother Thomas made a prudent entry into the marine insurance business, at a time when Britain's overseas trade was expanding at a prodigious rate. By the end of the 18th Century they had built up large fortunes.
After a serious setback caused by the economic slump in the aftermath of the Napoleonic Wars in the early 19th Century, business recovered and by the time the brothers died in the 1830s they were both, in today's terms, multi-millionaires. Their descendants kept the family businesses running successfully for several decades and diversified into agriculture, literature and politics, but the 1860s recession saw the end of the great wealth the Gregs and their associates had built up.