The Porum Range War:
Sometime in the 1880s, four sons of John Davis and Jane Tate---Samuel Tate (Sam), Cicero, John (Jack), and Robert Lee (Bob)---moved to the Cherokee Nation in Indian Territory and settled near Porum in Canadian District. The Davis brothers, in time, built modest homes and prospered as cattle ranchers.
But in 1906, only a year before Oklahoma statehood, a feud started between the Davises and Thomas L. Hester, a rancher, living near the Davis brother's ranches. The friction escalated into a war of violence and bloodshed...
On the evening of September 11, 1906, Cicero Davis was ambushed and shot dead from his horse as he rode along a dark stretch of road near his home. Mack Alfred was arrested for the murder but was acquitted.
On July 28, 1907 Mack Alfred was shot and killed just before he was to go before the grand jury and testify against Robert 'Bob' Davis in another case involving murder and robbery.
On May 4, 1911 Deputy Sheriff Jim Work was shot and killed. Bob Davis, Leonard McCullough and Amon Davis were charged but due to lack of witnesses and insufficient evidence the charges were dropped against Leonard and Amon and Bob was later acquitted.
No less than nineteen men lost their lives during the Porum Range War......

From an interview with a reporter for the Coffeyville Dailey Journal--Coffeyville, Kansas--May 15, 1912..

Jack Davis is the most picturesque member. He is a big fellow, weighing 240 pounds, with the ruddy look of a man who has lived an outdoor life. His eyes are dark and piercing, and he wears a black mustache. He has an air of assurance—something of the effrontery of the rule, raised early on the range. He has the old primitive ideas of justice that he learned in youth. At times he demands that his own interpretation of what is right shall take place of the law. Thus, he took the law into his own hands and shot Maxwell and McCullough.