Their roots and nomenclature are European and their acceptance worldwide, but, like the immigrants who were such a big part of their development, jeans found their true home in America.

Jeans derive their name from Genoa, Italy, where a variation of the city’s famous corduroy fabric caught on with sailors, who spread it throughout Europe. Further experimentation would lead to the development of the rigid cotton fabric today known as denim, for the French city of Nimes. Fashion historians agree that jeans found their way to the U.S. not long after the country declared its independence from Great Britain, giving it an American lifespan as well as an American heritage.

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And the heritage parallels that of the U.S., too, with jeans spending their first 150 or so years in America as a rugged, utilitarian workhorse, moving beyond the farms to big cities while the Industrial Revolution took hold and expanded westward as the population pushed beyond the Mississippi River in search of opportunity and fortune. Prospectors and ranch hands took to the sturdy bottoms just as the farmers and factory workers of the East had, giving Bavarian immigrant Levi Strauss a chance to expand his San Francisco dry goods business, founded during the height of the California Gold Rush with pants fashioned originally from tent fabric and, beginning in 1873, with riveted work pants made from denim and with a button front that remains in fashion today as style 501. Last year, U.S. retail sales of adult jeans totaled $13.51 billion, according to The NPD Group, with 57.7 percent of the volume attributable to women.

This story first appeared in the September 7, 2012 issue of WWD. Subscribe Today.

Enterprises similar to Levi’s developed in other parts of the country as the 19th century drew to a close. Henry David Lee founded the Lee Mercantile Co. in Salinas, Kan., in 1889 and, while best known for jumpsuits and overalls, introduced a fly-front jean in the Twenties. Wrangler Jeans had its roots in North Carolina as an overall maker in the early days of the 20th century. Wrangler would forever tie its fortunes to the western crowd when, just after World War II, it hired Rodeo Ben — born Bernard Lichtenstein, a tailor who immigrated to the U.S. from Poland — to focus on designing jeans for cowboys.

Jeans were destined for a larger role than the workwear function initially assigned to them. The emergence of a strong counterculture in the mid-Sixties brought jeans to a new generation, one that embraced the working-class roots of the item. Recognizing the strong links between antiwar protests, an explosive rock music scene and fashion, Levi’s put Jefferson Airplane into the recording studio to tape a commercial.

“At every point in its history, starting with the Gold Rush, Levi’s has placed itself on the edge of the modern frontier,” said James Curleigh, a lifelong wearer of the brand who became its president in May. “It’s never not been relevant and never not been functional, durable and practical. We have a saying here that, at Woodstock, those that weren’t naked wore Levi’s and those that were had Levi’s.”

Looking for a piece of the denim action on the street, retailers rushed to capitalize on the trend. Real estate executive Donald Fisher saw an opportunity to build a specialty store business dedicated to selling Levi’s and other products with a countercultural edge. The Gap, named for the growing divide between the generations, was founded in San Francisco in 1969 and would eventually grow into the largest U.S.-based specialty store chain, although it would ultimately focus on its own brands in order to do so.

Once the basic jeans makers laid the foundation, the fashion merchants rushed in, armed with sexier fits, alternative looks and, beginning in the late Seventies, big advertising budgets. Calvin Klein, Jordache, Sasson, Gloria Vanderbilt, Guess and Sergio Valente are among the first to put marketing muscle behind their bottoms, pushing retailers to buy in and avail themselves of presold consumers.

The jeans explosion was hardly lost on the Europeans, who took note of the sometimes usurious prices European consumers were willing to pay for Levi’s and other U.S. brands. In time, strong denim pockets would develop in Italy, England, France, Sweden and the Netherlands, and the influence of European brands helped usher in the premium denim explosion that had its roots in the Nineties.

John Eshaya, founder of Jet, had a front-row seat for the development of the premium market and the emergence of U.S. brands — most with California addresses and many with U.S. production — like Seven For All Mankind, True Religion, J Brand, Citizens of Humanity, Frankie B., Hudson, Earl and Current/Elliott during his years as vice president of women’s wear at Ron Herman.

“In the [early] 2000s, people had money to spend and they were willing to pay $200 or $250 for a pair of jeans,” he said. “It wasn’t about a designer name; it was about a great fit, whether skinny or boot-cut, and a great wash, about a great pair of jeans that elevated the T-shirts and sweaters it was being worn with.”

He noted how jeans in various stages of their history as an American fashion item generally evolve from dark basics to faded and worn looks, then into color and novelty before returning to their darker, more basic roots, as they have recently. “Premium isn’t that much unlike other parts of the history of the denim business — not high fashion but everyday wear.”