Marquess Grey is a title that was created in the Peerage of Great Britain on 19 May 1740 for Henry Grey, 1st Duke of Kent, with remainder to the male issue of his body and in default thereof to his granddaughter, the Honourable Jemima Campbell, and the heirs male of her body.

He was succeeded in the barony of Lucas (which could be passed on through female lines) and in the marquessate of Grey according to the special remainder by his granddaughter Jemima, who became the second Marchioness Grey.

She was the daughter of John Campbell, Lord Glenorchy, later 3rd Earl of Breadalbane and Holland, and Lady Amabel Grey (died 1726), eldest daughter of the Duke of Kent.

On 22 May 1740, three days after the marquessate was created, she married the Honourable Philip Yorke, later 2nd Earl of Hardwicke.

[2] However, she was succeeded in the barony of Lucas by her elder daughter, Lady Amabel, who in 1816 was created Countess de Grey in her own right (see Earl de Grey for further history of this title).