1869, when Ned Buntline wrote the first Buffalo Bill dime novel:
That means the “Wild West” era began in popular culture before the cowboy era we now call the Wild West. The power of myth.
It’s like asking when the “Dark Ages” ended. They kind of didn’t exist in the first place. At least in the sense we typically mean of a vast internecine stretch of barbarism between periods of relative civilization.
Yes, there was a frontier in the west. But the concept of a “Wild” west was vastly overblown. I.E. Butch and Sundance were performing their antics in a relatively civilized, though still frontier-ish, west, not the thoroughly wild one of fiction. That a gang of bank robbers existed doesn’t make the west wild. Otherwise, Depression era gangs like Bonnie and Clyde’s would be a strange aberration.
The Wiki page for Buffalo Bill and other sources seem to agree on what Exapno Mapcase wrote, except that they seem to suggest that Buffalo Bill already had his nickname a few years before Buntline began writing those novels with the “Buffalo Bill” main character. From a PBS article on the subject, for example (the Wiki page has the same story):
But I didn’t realize that the legends about him had begun that early. The Wiki article mentions:
(Emphasis mine.) Right: Something happened to Western (formerly Latin) Europe from 500 CE through 1500 CE, give or take a century here or there. Just because it wasn’t a zombie apocalypse or a thousand years without sunlight or something similarly obvious doesn’t mean nothing changed when the Roman Empire pulled back from former strongholds and let infrastructure decay.
Historiography has changed. Our understanding of concepts like “civilization” and “progress” has changed. The old understanding of the Friendly Neighborhood Roman Legion going away and being replaced by Lord Hungus is, in retrospect, wrong if taken as an absolute generalization. However, the British, for example, had a pretty rough time of it after the Romans left and the Saxons invaded. Other regions went through similar upheaval during the Migration Period. Bad things happened. Written records were lost or never made, due to the social collapses. Our records do indeed go quite dark in some places.
So we see a parallel, in that there were a few events which did happen but then got blown out of proportion and used to tar a whole period and reduce it to a broad caricature of itself.
Agree with the 1890 date. I remember that being given in my US History class in college.
I would be delighted, were I to learn of Dan Brown writing a novel with the title The Buffalo Bill Code. I might even check it out at the library and read it. 
Barbed wire is what really tamed the West.
L.A. County still had a lot of agriculture through the first half of the 20th Century. According to my dad, who moved there with his family in the early 1930s, some of the ranch hands would still come into town on the weekends, for a Saturday evening’s amusement. First stop might be a bathhouse, of which a few still existed; these were primarily for bathing and cleanliness with nothing else on the agenda. Bath time over, the dive bars, burlesque houses, the red light district (not that it was legal by then, of course), and maybe illicit gambling awaited. These men weren’t gunslingers or thugs by any means, but theirs was still a rough crowd and I’m sure bar fights and the like weren’t too unusual. And, it’s been observed before that the settling of disagreements by means of stand-up fights used to be more common and more acceptable than it is today.
So you had a situation where there were still some of the lifestyle patterns of the Old West existed, if not necessarily the stereotypical degree of lawlessness. I think it’s safe to say the dividing line between one era and the next was vague at best.
Yes, cowboys are, and were, a type of farm laborer. Like other jobs, they have gathered a certain mystique and a set of stereotypes, most of which have some basis in reality but are, of course, significantly exaggerated.
Real life cowboys were laborers. The cowboys in books and movies, though, tended to be ranch owners, not ranch hands. That gave them ownership, i.e. a fixed stake in the land, as well as money, power, prestige, and the tools of their trade. The parallel is not exact, but you can think of media cowboys as the ancestors to the crews in Star Trek. There are the upper class, the cowboys/officers, who have all the adventures and live to participate in the next one, and the lower class, the ranchhands/redshirts, who are in the plot to die picturesque deaths. That formula was perfect from the beginning and so never changed.
You also can make a Star Wars parallel, in which individual entrepreneurs have the freedom to go have adventures, so that Buffalo Bill equals Han Solo. Freedom remains the key point. They don’t have bosses telling them they need to do their chores.
So some of the Old (if not so Wild) West overlapped with Hollywood. I remember a Young Indiana Jones episode in which Indy worked on a John Ford silent. And was amazed to meet Wyatt Earp.
Two of Wyatt Earp’s pallbearers (in 1929) were Western film actors, Tom Mix and William S. Hart. The change from truth to myth seems to have been incredibly rapid.
The arrival of families was probably the largest factor in “taming” the west. (And yes, the traditional lore is overblown). When it is mostly men driving cattle, fighting Indians, or prospecting for gold, there are towns that spring up to provide supplies to these men. These men are also interested in saloons, whorehouses, and gambling. When men get drunk, they tend to fight.
When wives show up they put a stop to all that shit, posthaste. This fine tradition continues to the present. 
Until the 1950s, Los Angeles County was the top agricultural county in the nation.
This. 1880-1890 is a good time-period for the rapid spread of this new technology, and it is what effectively ended the open range aspect of the Wild West. 1884 and the end of the Fence Cutter’s Wars in Texas, for a precise year.
The start date was the question I had while reading this thread. It always amazes me how short the time period was that is represented by so much of our “cowboys and Indians” cultural memory. The pony express and cattle drives lasted for ridiculously short periods. Lewis and Clark was in 1803. The gold strike in '49. The transcontinental railroad in the 60s. The Indian wars primarily after the Civil War.
I’d probably put the start date closer to 1849, when large numbers of people started traversing the plains. If we accept an end date of 1900, that would be a MAXIMUM of 50 years. More realistically, I’d estimate the "high " western age to have been far shorter - maybe from 1870-95 at the most. An awfully short period, given the primacy so much of the imagery continues to have in American minds.
1849 did see large numbers traversing the plains, but the key word there is traversing. The plains were places of misery and death to be crossed as quickly as possible to get to California for the Gold Rush. I’m sure a few people got stopped along the way but not a historically important number.
The wagon train era had already started by then, with the Oregon Territory under control by 1846. Thousands of cattle were moved west with them. The cattle greatly outnumbered the people.
Your personal definition counts most. Do these small starts get included or does the era wait until after the Civil War when the remnants of Union troops were put into the Indian wars to “pacify” the territory for settlers?
The ending is even fuzzier. You could pick dates anywhere from 1890 with Wounded Knee to the beginning of WWI.
Western civilization ended? I must have missed it. I thought I was living in it.
Though I know it was in decline for a while, but it picked up again.
As for cowboys, at least in the time of Tombstone , AZ: “In that time and region, the term “cowboy” generally meant an outlaw. Legitimate cowmen were referred to as cattle herders or ranchers.”
I always thought the Wild West ended when the various territories were finally incorporated into States.
The absolute last gasp of the Wild West may have been Pancho Villa’s “bandito” raid against Columbus, New Mexico in 1916, and the famous(ly failed) US Army expedition against him that ended when the US entered World War One in 1917.