ARE DEMIM BLUE JEANS REALLY AN AMERICAN CREATION?

Yup! But, like apple pie, it's origins can be traced elsewhere.

For thousands of years Indigo, a blue dye original produced in India, was used to dye cottons and other fabrics. During the 1600's, Europeans began to use it the production of their everyday fabrics. Two different versions eventually came to the for-front and are thought to have been named after the cities in which they originated. One was jean, from Genoa Italy, and the other was denim from (de) Nimes France. The jean fabric was made of two pieces of Indigo dyed strands of cotton woven together. The denim fabric was made from one piece of heavier white cotton woven with a strand of the blue dyed cotton. The denim proved to be sturdier and was therefor used for more utilitarian clothing, while the jean material was better suited for lighter wear.
As Genoa (a placed I lived when I was in Italy!) was a large Italian port city, many sailors who docked there were introduced to clothing made out of  this rugged and inexpensive denim fabric. It quickly spread in popularity and was used in clothing in many countries throughout Europe.
As the American continent was settle and goods began to be transported from Europe, denim and jean fabrics came too. Denim was known for being and hardworking material and something called the denim overall was widely used by farmers, mechanics and industrial workers.