With Borgward promising to revive the brand with an SUV concept ready for this fall, Petrolicious thought the time was right for a closer look at post-war Germany’s most intriguing car maker. Before it was forced to shut its gates in 1961, Borgward employed more than 23,000 people and made one of the fastest mid-sized cars on the road, the Isabella TS. It invented the mid-sized sports sedan years before BMW did. But it hasn’t made a car since. So what happened?