The Model T was easy to operate, maintain, and handle on rough roads. It immediately became a huge success. Ford could easily sell all he could make; but he wanted to make all he could sell. Doing that required a bigger factory. In 1910 the company moved into a huge new plant in Highland Park, Michigan, just north of Detroit. There Ford Motor Company began an relentless drive to increase production and lower costs. Henry and his team borrowed concepts from watch makers, gun makers, bicycle makers, and meat packers, mixed them with their own ideas and by late 1913 they had developed a moving assembly line for automobiles. But Ford workers objected to the never-ending, repetitive work on the new line. Turnover was so high that the company had to hire 53,000 people a year to keep 14,000 jobs filled. Henry responded with his boldest innovation ever—in January 1914 he virtually doubled wages to $5 per day.

At a stroke he stabilized his workforce and gave workers the ability to buy the very cars they made. Model T sales rose steadily as the price dropped. By 1922 half the cars in America were Model Ts and a new two-passenger runabout could be had for as little as $269.

In 1919, tired of “interference” from the other investors in the company, Henry determined to buy them all out. The result was several new Detroit millionaires and a Henry Ford who was the sole owner of the world’s largest automobile company. Ford named his 26-year old son Edsel as president, but it was Henry who really ran things. Absolute power did not bring wisdom, however.

Success had convinced him of the superiority of his own intuition, and he continued to believe that the Model T was the car most people wanted. He ignored the growing popularity of more expensive but more stylish and comfortable cars like the Chevrolet, and would not listen to Edsel and other Ford executives when they said it was time for a new model.

By the late 1920s even Henry Ford could no longer ignore the declining sales figures. In 1927 he reluctantly shut down the Model T assembly lines and began designing an all new car. It appeared in December of 1927 and was such a departure from the old Ford that the company went back to the beginning of the alphabet for a name—they called it the Model A.

The new car would not be produced at Highland Park. In 1917 Ford had started construction on an even bigger factory on the Rouge River in Dearborn, Michigan. Iron ore and coal were brought in on Great Lakes steamers and by railroad. By 1927, all steps in the manufacturing process from refining raw materials to final assembly of the automobile took place at the vast Rouge Plant, characterizing Henry Ford’s idea of mass production. In time it would become the world’s largest factory, making not only cars but the steel, glass, tires, and other components that went into the cars.

Henry Ford’s intuitive decision making and one-man control were no longer the formula for success. The Model A was competitive for only four years before being replaced by a newer design. In 1932, at age 69 Ford introduced his last great automotive innovation, the lightweight, inexpensive V8 engine. Even this was not enough to halt his company’s decline. By 1936 Ford Motor Company had fallen to third place in the US market, behind both General Motors and Chrysler Corporation.

In addition to troubles in the marketplace, Ford experienced troubles in the workplace. Struggling during the Great Depression, Ford was forced to lower wages and lay off workers. When the United Auto Workers Union tried to organize Ford Motor Company, Henry wanted no part of such “interference” in running his company. He fought back with intimidation and violence, but was ultimately forced to sign a union contract in 1941.

When World War II began in 1939 Ford, who always hated war, fought to keep the United States from taking sides. But after the Japanese attack on Pearl Harbor Ford Motor Company became one of the major US military contractors, supplying airplanes, engines, jeeps and tanks.

The influence of the aging Henry Ford, however, was declining. Edsel Ford died in 1943 and two year later Henry officially turned over control of the company to Henry II, Edsel’s son. Henry I retired to Fair Lane, his estate in Dearborn, where he died on April 7, 1947 at age 83.