Heck Thomas Henry Andrew " Heck " Thomas ( January 3 , 1850 – August 14 , 1912 ) was a lawman on the American frontier , most notably in Oklahoma . Biography . Thomas was born in 1850 in Oxford , Georgia , the youngest of five children of Martha Ann Fullwood ( " née " Bedell ) and Lovick Pierce Thomas , I . At the beginning of the American Civil War , Thomas , at the age of twelve , accompanied as a courier his uncle , Edward Lloyd Thomas , and his father , who were officers in the 35th Georgia Infantry , to the battlefields in Virginia . On September 1 , 1862 , Union General Philip Kearny was killed at the Battle of Chantilly , Young " Heck " was entrusted with the general ' s horse and equipment and was ordered by Confederate General Robert E . Lee to take them through the lines to General Kearny ' s widow . He recounted this in a letter to his brother Lovick Pierce Thomas , II : In 1863 , Thomas contracted typhoid fever and returned to his family in Athens . As a young man he clerked in the store in Atlanta of his brother , Lovick Pierce Thomas , II , and then worked as an Atlanta policeman . In 1871 , he married Isabel Gray . He and his family migrated to Texas in 1875 and with the help of his cousin , Jim Thomas , obtained a job with the railroad as a guard . Thomas became a railroad detective and later went to work for the Fort Worth Detective Association . He was appointed U . S . Deputy Marshal out of Fort Smith , Arkansas , working under U . S . District Judge Isaac C . Parker . By 1889 Thomas teamed with two other deputy U . S . marshals , Chris Madsen and Bill Tilghman . They became known as the Three Guardsmen and were credited with bringing law and order to the Indian Territory , in the state that would become Oklahoma in 1907 . The Three Guardsmen were credited with the apprehension of more than three hundred outlaws over the next decade , killing several . They were credited with the ultimate demise of the Wild Bunch or Doolin Gang . Thomas was specifically mentioned by Emmett Dalton , years after his release from prison , as one of the main reasons the Dalton Gang chose to commit two simultaneous bank robberies in Coffeyville in southeastern Kansas , stating that Thomas was relentless in his pursuit , and the gang decided to make one big score , and leave the territory for a time . Instead , the gang was wiped out in the Coffeyville robberies , with Emmett Dalton being the only survivor . In August , 1896 , Thomas lead a posse that tracked down and killed outlaw Bill Doolin , who had previously been captured by Tilghman , only to escape from prison on July 5 , 1896 . By 1902 , much of Oklahoma had been settled . Thomas was sent to Lawton , where he was elected as the first police chief in the town . He served in that position for seven years until his health began to fail . Showing his lighter side , Heck assembled a posse , chased and captured bank robbers in the 1908 film " The Bank Robbery " . The outlaws were led by Al Jennings , while the one - reel movie was directed by Bill Tilghman , James Bennie Kent was the cinema - photographer , and it was produced by the Oklahoma Natural Mutoscene Company . The film was shot in Cache , Oklahoma , and at the Wichita Mountains Wildlife Refuge , with Quanah Parker having a bit part . A bystander thought that the bank was really being robbed and jumped out a window to run for the police . Thomas died in Lawton , Oklahoma on August 14 , 1912 of Bright ' s disease .