Photo journal: Rise and fall of mass production

Ford was even more determined to resist unions than GM, and Henry Ford employed 3,000 “service department” personnel to prevent them taking hold.

In 1937 they beat up key UAW union organisers attempting to hand out leaflets near the River Rouge factory.

But in 1941, even Ford was forced to yield to union power, to ensure industrial peace during wartime.

But the legacy of bitter industrial relations endured.