Jemima was married to Sir Charles Cornwallis, 1st Marquess Cornwallis. He had a successful military career, except for being trapped on the Yorktown Peninsula of Virginia where he and 4000 troops surrendered to a Franco-American force to effectively end the colonists' revolution in the Americans favor. He served in India with distinction as well as in North America. According to her article in thepeerage, they had a son and daughter.
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