Billy The Kid
Billy the Kid's real name was William Henry McCarty, Jr. He was a 19th-century Irish American gunman who participated in the Lincoln Country War and he became a popular outlaw in the American West. According to legend he killed 21 men, but it is generally believed that he killed 8 people, the first one being killed in 1877 when William was just 18.
He was 5'8" tall with blue eyes, blonde hair (or dirty blonde hair) and a smooth complextion. He was desribed as friendly and personable at times, these qualities, along with his cunning and celebrated skill with firearms made him look both a notorious outlaw and a folk hero.
The Transcontinental Railroad
The US government had long wanted to build a transcontinental railroad to link East and West. In the 1860s, two companies started building, one from the East, and one from the West. Eventually they met in Utah.
This made it easier for homesteaders to get to the Plains, it was also cheap to buy land, as the railroad companies sold off the land on either side of the line at low prices. The result of this was there was a flood of homesteaders moving to the Plains. It also resulted in the killing of the buffalo herds as trains were set up to travel along and kill them.