1. Pontiac – In theory, it was GM’s performance brand. We’ll miss cars like the G8,GTO and Solstice GXP; we wish we could erase the Aztek from our memory (as did Pontiac, no doubt).
2. Mercury – Founded in 1939 by Henry Ford’s son, Edsel, Mercury most recently served as an example of poor badge engineering.
3. Saturn – Originally known for its plastic-bodied cars and “no-haggle” dealer model; severely held back by a lack of new and unique product.
4. Hummer – Thrust into pop culture by a muscle-bound Austrian-born actor/governor, these off-road-biased trucks proved far too bulky and inefficient for the times.

If there’s one constant in this world, it’s this: We live in a world of constant flux. In the automotive world, however, we’ve all grown accustomed to seeing the same group of manufacturers introduce new models each year. You know the names. But for the 2011 model year—thanks largely to the huge economic downturn that began in late 2008—four well-known American nameplates have gone the way of the Edsel, so to speak.

Of these four, the Hummer brand was the most short-lived. The original Hummer H1 (or Hum-Vee) was a celebrity of the Persian Gulf War. In 2002 came a smaller and (slightly) more manageable version, the Hummer H2. Exactly what made suburbanites decide they needed a four-wheeled facsimile of a machine-gun toting, troop-hauling war machine parked in their driveway is best left to future generations to explain. Perhaps the supersized and fuel-guzzling excess of the Hummer brand will someday look as quaint as towering tailfins from the late-1950s? Or perhaps not.

Pontiac and Mercury always maintained a far more balanced product portfolio during their much longer life-spans. Founded in 1939, Pontiac was introduced as a companion make to prop up sales at GM’s Oakland division. Pontiac immediately outsold, and eventually far outlived, its parent brand. Oakland faded away in 1931. Pontiac’s historical highlights include the 1964 Pontiac GTO (the car that defined the muscle-car era) and the Firebird sports coupe.

Mercury was introduced in 1939, not to boost another brand’s sales, but to fill the price gap that had emerged between Ford and its upscale sibling, Lincoln. Cars like the 1949 Mercury Coupe driven by James Dean in Rebel Without a Cause all but guarantees the brand immortality – even if the nameplate itself has finally driven into the sunset. Years of badge engineering eventually dissolved Mercury’s identity, squeezing the brand out of the Ford Motor Company family tree.

Perhaps the biggest surprise – at least in terms of positive automotive karma – is the loss of Saturn. Created by GM to take the fight to imports, Saturn was marketed as “a different kind of car company,” thanks to a lineup of fuel-sipping small cars and no-haggle pricing policy. If only the cars lived up to the feel good dealership experience. A lack of development and new models left Saturn spinning out of orbit. A list ditch effort to market vehicles built by GM’s German-based Opel division as Saturns proved too little too late.