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The Duchess (edition 1991)
The Duchess by Jude Deveraux
References to this work on external resources.
Wikipedia in English
Amazon.com Product Description (ISBN 067168972X, Mass Market Paperback)
Claire Willoughby risked losing millions in her inheritance if, as decreed by her grandfather, she did not wed an "acceptable" man. Harry Montgomery, the eleventh Duke of MacArran, seemed perfect. He owned a historic castle, he looked manly in a kilt, and he was as much a titled Scotsman as Bonnie Prince Charlie himself.
Their engagement announced, Claire's future as a duchess was assured -- and she set off with her family to meet the Montgomery clan in Scotland. Bramley Castle was a damp, chill place, overÞowing with eccentric relatives. But there was also Trevelyan, a secretive, brooding man who lived in Bramley's ancient halls. Whoever he was, he wasn't at all like Harry: Trevelyan was the most exasperating, arrogant, know-it-all of a man Claire had ever met. And the most fascinating...
(retrieved from Amazon Thu, 12 Mar 2015 18:19:42 -0400)
In order to secure her inheritance from her grandfather, Clair Willoughby has agreed to marry Harry Montgomery, but when she goes to meet his family at Bramley Castle, she meets the fascinating and very mysterious Trevelyan.
(summary from another edition)