Factors of jeans

In my topic, my thesis is fashion which includes history, designer, customer, and other factors. I think I find factors which I think are really important for my research. In my recently work, I focus on the fashion brands’ history. http://www.levistrauss.com/Heritage/History.aspx, this is the Levis official site which could give much information about how Levis invented the first jeans in the world and how Levis, this company become to a famous popular clothing brand.
Through this brand’s history, I am trying to analyze the factors which have significant influent on the fashion. In 1873, the first blue jean was made by using denim which fabric’s firmness is better than the general cotton fabric. During 1870 to 1890, there was Califomia Gold Rush time, a lot of people went to Califomia and looked for their fortunes. However, their pants were unable to suffer from the poor conditions when they were working in the diggings. The miners needed pants which not only could protect their body from being harm, but also needed pants with better durable. The jeans could meet their demand. Miners were more willing to wear jeans because jeans could help them working in the mine. Therefore, people accepted jeans because jeans have better quality, like Levis ad “quality never goes out of style”. We can see that quality is prerequisite to decide whether be accept by people. Therefore, quality is an important factor to which influent fashion and fashion brands. Also I think opportunity is another factor which can influence fashion. Jeans were made at the Califomia Gold Rush, and at that time, there is no TV, and Internet, so people bought jeans because others gave positive comments. If there was no Califomia Gold Rush, people did not have much need of jeans, I do not think jeans could be popular so fast and could spread out around the America.