The name Seville was first used in the Cadillac lineup in 1956. Cadillac had introduced its top-of-the-range, ultra luxurious Eldorado as a limited production car in 1953. At the then staggering price of $7750 (a Coupe de Ville cost $3995 and a Convertible $4144), only 532 were sold. The next year, the Eldorado was in fact a specially trimmed convertible and its price was reduced by more than $2000. In 1956, Cadillac decided to bring out a hardtop version of the Eldorado. To distinguish between the two models, the convertible was called Eldorado Biarritz and the hardtop got the name Eldorado Seville. So as a matter of fact, the first Sevilles were not four door sedans, as we know them today, but ultra-luxurious two door hardtop coupes. The 1956 Eldorados stood out from the "regular" Cadillacs with a more performant engine. The Eldorados were equipped with two four-barrel carburaters (as opposed to one 4 bbl) and their engine was rated at 305 HP @ 4700 rpm. The other Cadillacs got a 285 HP engine. For 1957 and 1958 the Eldorados were even more distinguishable. They got their own tail fin treatment, known as shark fins. They protruded like sharp razor blades, from the slender down curving rear fender and were only a hint at the outrageous fins that would appear on all Cadillacs two years later. Again the Eldorados got a beefier engine with two four-barrel carbs. Only minor facelifts were applied on 1958 Cadillacs. All cars now had standard dual headlights and again some more chrome here and there. The automotive industry experienced its worst post-war recession and Cadillac's output dropped by 16% to 121,778 cars. Chrysler had given America big tailfins in 1957, but Cadillac was to "out-fin" every other car maker with its 1959 lineup. Each and every model sported huge razor sharp spacecraft-like tailfins. From each fin, two cone-shaped taillights emerged. If they were lit, nobody could do away with the resemblence to the exhaust flame of a rocket. Chrome was also abundantly present on these spaceships. As if the front grille did not shine enough already, Cadillac mounted a rear end grill, just beneath the trunk lid. Excentricity had reached its peak in 1959, and from then on the tailfins would diminish in size, just to disappear altogether in 1965. The Eldorados lost their own specific body shape and were now specially trimmed and better equipped versions of the Coupe and the Convertible. They also had a better performing engine (again 20 HP more than the standard one), but this time they had triple two-barrel carburators. 1960 was the last year for the name Seville to appear on a Cadillac until 1975.

By 1975 a lot had changed on the American car market. The Arab oil embargo of 1973 certainly had not done any good to those smooth running gigantic engines Cadillac used to put in its cars. Furthermore the imports were on the move, and the American buyers realized that they could get luxury cars from abroad. For Cadillac the toughest import to compete was Mercedes-Benz. And this latter reason was the main impulse for the development of the 1975 Seville.

Imports were a lot smaller than the gigantic Cadillacs that were floating over America's freeways in the early seventies, so Cadillac decided it should go for a "compact" car. Several alternatives were discussed in the early seventies, amongst them a retrimmed version of the Opel Diplomat. Eventually, taken into consideration the limited time available and the budget restrictions imposed by GM management, it was opted that the corporate X-body would be used as a basis for the new Seville. However, changes to this platform were so drastic that an all new designation was given to the body: the K-body. Halfway 1975 a new Cadillac appeared on the American market. At 27" shorter, 8" narrower and 800 lbs lighter than a regular DeVille, it truely was a revelation . This new Seville featured Oldsmobile's proven 350 cid V8, but was now equipped with electronic fuel injection, an industry first on the American market. Though it was the smallest Cadillac, it was nonetheless the most expensive one too (except for limited production Fleetwood 75 series). At a list price $12,479, it featured almost everything a man could dream of, plus a whole range of options and toys could be specially ordered. This car was still rear-wheel drive and did not even have independent rear suspension. It also got some criticism because of its rear drum brakes, but nevertheless this was a splendid automobile which gained a lot of praise all over the world. The Seville received its much asked for rear discs in 1977. As a matter of fact, surveys have later shown out that Cadillac succeeded in slowing down Mercedes-Benz' growth in the US, with the introduction of the 1975 Seville. In 1980 Cadillac had another surprise with its all new Seville. Reminding many people of the pre-war Hooper bodied Daimlers, the Seville sported now a razor sharp rear deck. This was a no-way-in-between car. Those who loved, loved it tremendously, those who hated it, hated it as much. At least, it was a recognizable car and is already now regarded as a classic by many collectors. It had many improvements over the previous Seville: front wheel drive and independent rear suspension amongst them. However, dark times were looming at the horizon for Cadillac, and it would take more than a decade for the GM flag division to rise to its former superiority.

The first problem arrived already in 1979 when GM, in a crash-program on fuel economy, started to put diesel engines in its cars. Even Cadillacs were delivered with 350 cid diesel V8's. These engines were soon renowned for being troublesome and unreliable. Furthermore, in 1981, Cadillac made available what should be the best-of-both-worlds: the V8-6-4. This was a variable displacement engine, running on 8, 6 or 4 cylinders, depending on power demands. On the drawing board this seemed a very good idea, however in practice it was disaster. Cars stalled in the middle of busy freeway traffic or while climbing steep hills. The only remedy was to cut two wires, in order to override the computer, so that the engine would always work in 8 cylinder mode. If all this was not bad enough, GM decided on a corporate downsizing for the 1985-86 model years. The 1986 Seville and Eldorado were the main victims of this unfortunate move. These two new cars were mere shadows of their predecessors. They were excellent cars in their own right though. They had excellent handling, great fuel economy, good reliability, but they simply did not look like Cadillacs. Looking back now, it is probably easy to criticize Cadillac management and design, but one must remember that the early eighties was an extremely difficult period for the American automotive industry. It was generally accepted that fuel prices would triple by the mid-eighties and all manufacturers were seeking alternatives to their still big cars. When fuel prices had only risen by a little bit in 1986, Cadillac presented its two new mouse-cars. The public did not like them, and Seville production plummeted from 39,755 to 19,098 units. From then on, Seville production would hover around 22,000 units for the next couple of years, except for 1991 (a healthy exception with 33,128 units). Starting in 1989 Cadillac attempted to make the Seville more attractive to a younger audience. As a move to get some potential BMW or Audi customers, a special de-chromed sporty version of the Seville was available: the STS . A special touring suspension had been available on the Seville in earlier years, but now the car had its own look. This is the first time in Cadillac history that the STS designation would appear. It is not enterily clear whether STS stands for Seville Touring Sedan, Sport Touring Sedan, Seville Touring Suspension or Sport Touring Suspension , but the idea was OK. This was only a minor indication of what was to come in the all-new Seville for 1992.

GM realized that they had gone the wrong way with Cadillac, and a complete line restyle was due for 1992-1993. The first two cars to change were the 1992 Seville and Eldorado. Significantly larger than their predecessors, the new Seville/Eldorado pair was the talk of the automotive industry. They still featured the classic 4.9 liter pushrod V8, found in all other front wheel drive Cadillacs, as engineering found it wise to delay production of the long awaited Northstar for another year. The car's interior was an instant hit. Even BMW design was surprised why they had not thought of this kind of interior. From the outside the new Seville (especially the STS), looked mean and aggressive, but also distinctive and restrained. The public loved it as much as the press and sales rose to over 43,000 for the 1992 model year. In 1993 Cadillac finally made available the Northstar system. This made the Seville and the Eldorado the best performing front wheel drive vehicles in the world.