The Mercury Marquis is a model line of automobiles marketed by Mercury from 1967 to 1986. Deriving its name from a title of French nobility, the Marquis was introduced as the divisional counterpart of the Ford LTD; four generations of the two model lines were paired through rebranding. Initially slotted as the flagship Mercury full-size range, the Marquis would serve as the basis for the later Mercury Grand Marquis.

The Ford LTD is a range of automobiles manufactured by Ford for the 1965 to 1986 model years. Introduced as the highest trim level of the full-size Ford model range, the LTD moved the Ford range upmarket, offering options and features previously reserved for Mercury and Lincoln vehicles. For much of its production life, the LTD competed against the Chevrolet Caprice ; the Mercury Marquis served as its divisional counterpart from 1967 until 1986.