I don't understand your question. How did the 1860s come to be regarded as the time when the West a was wild? I'm not sure that's the case any more than other decades. What was the nature of the West in the 1860s? That's complicated because there were two Wests in the decade - during and after the Civil War, which affected the entire region. But the region was large, so one must keep in mind that there were many Wests and many ways to answer a general question. But before there can be an answer, your question must be clear.