Contrary to the impression left by Western movies, homicides were rare in the Wild West
In 1880, wide-open towns like Virginia City, Leadville or Dallas had no homicides. Compare this to Cincinnati, in the 'civilized' state of Ohio, which had 17 homicides in that same year.
Virginia city had 8 homicides during the year-and-half following its founding in 1859. In 1876, the year of its birth, Deadwood had 4 homicides. Ellsworth, one of the Kansas cattle towns, had 8 homicides during the twelve months following its establishment in 1867, and Dodge city, the queen of the cattle towns, had 9 in its first year, 1872-1873. (Note: this number of nine homicdes from Frontier Violence: Another Look, author W. Eugene Hollon does not agree with the number given below.)
From 1870 to 1885, the fabled cattle towns of Abilene, Caldwell, Dodge City, Ellsworth and Wichita had a total of 45 homicides between them - an average of three per year spread over five towns, or roughly one killing every one-and-half years per town. Sixteen of these 45 homicides were committed by duly authorized peace officers. Some of these were domestic quarrels.
The population of Dodge City was never much more than 3,000. In its worst year (1876), Dodge City had 5 killings. This translates to approximately 1 murder per 600 residents per year. Remember, this is 'the worst year'. To keep everything in perspective, consider that in Abilene, supposedly one of the wildest of the cow towns, not a single person was killed in 1869 or 1870.
One homicide per 600 residents would translate to 5000 homicides in a city the size of Chicago, with a population of approx. 3 million.
Sounds awfully high, but it all depends on your perspective.
Most city suburbs have a population greater than 3000, and to have 5 killings in a small suburb of a size comparable to taht of Dodge city would be considered horrendous.
On the other hand, six or seven weekends in Chicago in 2012 can leave 45 homicides - it took 15 years and 5 cattle towns to reach that figure in the Wild West. Then consider Cincinnati again which in one year (1880) had 18 homicides.
In conclusion it looks as if the Wild West was a relatively safe place to be.