davis, who needs capital and manpower, goes into business with wealthy san francisco merchant levi straussay 20, 1873, american blue jeans are born. a pair costs about a buck. levi's markets their denim overalls as the uniform of the working class. >> who bought them at the time? >> miners in the west, farmers, mechanics -- anybody that did hard labor would have bought levi's back then. >> that's because workers love how tough and durable the pants are, as this pair from 1890 proves. >> from the 1800s? i mean, they feel like they could be right now. they really could withstand a lot. >> absolutely. >> so it was all about strength? >> it was all about strength. >> now, here's something really important to remember in this "strange inheritance" tale. in 1906, the epic san francisco earthquake devastates the levi's headquarters... >> their building, it was completely leveled. >> ...along with all of levi's records and inventory. the first 30 years of the company's history -- gone. of course, for the next century and more, the company thrives. indeed, the pants it manufactures become an americ