Landau, when used in referencing an automobile, generally means a simulated convertible.
It is originally a coachbuilding term for a type of carriage; see Landau (carriage). Many coachbuilding terms transferred over to automobile usage, since coachbuilders began making motor car bodies instead, and because customers were familiar with coachbuilding terms. The landau, however, was not a style that transferred well to the automobile. A forward view was generally insisted upon by passengers, so the half-landau ([landaulet]]) style became a more popular choice than the true landau. The landaulet opens over the rear seats, but not the front. Some of these vehicles were inaccurately described as "landaus".
In the 1920s and 1930s, especially in the United States, the term "landau" became used for a simulated convertible, in which a fixed roof of a sedan with solid rear quarters was covered with fabric or leather and fitted with side landau bars to make it appear like a convertible top. This became the commonly accepted definition of "landau" in North American usage thereafter.
After World War II, the term fell into disuse. However, landau became a model name when Nash Motors introduced the Rambler in 1950. The new compact car was available during its first year of production only as a "convertible landau".[1] The Rambler's canvas top opened from the windshield header all the way to the back and stowed in the trunk area. This unique convertible design featured steel framed roof rails around the car's side windows. The Rambler's strong body structure eliminated the internal bracing that was normally needed on other open cars. Essentially it was a cabrio coach.
The term was used to describe hardtop designs during the late-1950s.[2]
The landau description was revived during the 1960s. There was a trend for making "fake convertibles" by applying vinyl roofs on regular cars. Some of these vehicles were called "landaus" by their manufacturers, and many were fitted with landau bars on the rear quarters (faux cabriolet). Some used the term "Town Landau", and this generally meant a wider rear pillar with no rear quarter windows, or a partial vinyl roof that was applied only over the rear seat area (and is thus reminiscent of a town car).
A landau roof is also commonly used on the North American hearse; very long closed rear quarters, a vinyl roof, and huge, polished landau bars have been the preferred hearse style since before World War II.