In this day and age, the general public is pretty aware of the sadistic crimes committed by a handful of American serial killers. We all know about Jeffrey Dahmer, John Wayne Gacy, and Ted Bundy, but what about serial killers of the 19th Century?

The United States of America's so-called first serial killer is widely considered to be H.H. Holmes, a man who ran a hotel where many patrons checked in, but never checked out.

However, by today's definition of what makes a person a serial killer, another man with many ties to Colorado, including his final resting place, might be considered to be another one of the country's earliest serial killers. Keep scrolling to learn about Tom Horn Jr. and decide for yourself.

Colorado Cowboy or Serial Killer: Who Was Tom Horn?

Get our free mobile app

Tom Horn Jr. was born on November 21st, 1860 to an allegedly physically abusive father and by the time of his death on November 20th, 1903, was believed to have killed at least 17 people.

Horn allegedly killed a member of the Mexican Army in a duel over a disagreement over a prostitute while rather young, which was followed by a stint in the United States Cavalry where he killed numerous Native Americans during an ambush.

However, it wasn't until Horn became a cattle rancher and was robbed of all of his livestock within a short period of time that he would lose all remorse and feelings for other humans' lives.

Was Colorado's Tom Horn an Actual Serial Killer?

According to Wikipedia:

A serial killer is typically a person who murders three or more persons, with the murders taking place over more than a month and including a significant period of time between them.

From this definition, what Tom Horn did as a hired gun after losing all of his livestock would likely put him into this category.

Tom Horn began a bloody career as a man who was known to shoot and kill anyone he suspected of cattle rustling or theft on site, with no remorse and no consideration for human life.

Horn was known as an assassin and got away with numerous murders, primarily involving livestock theft but not always. He said he was killing for money, but others described Horn as having a "wicked streak" and claimed that the man enjoyed ending another's life.

Horn would eventually drunkenly admit to the murder of a 14-year-old boy, a confession that is disputed to this day by many, and was hanged on November 20, 1903, one day before his 43rd birthday.

Tom Horn is currently buried in Boulder Colorado at the city's Columbia Cemetery.

See 12 Unique + Often Scary Colorado Cemeteries and Memorials

Some are historic, some are scary, but each one of these Colorado cemeteries and memorials is definitely unique.

Gallery Credit: Nate Wilde

Tales of Dancing Orbs + Glowing Graves at Old Colorado Cemetery

One of Colorado’s oldest cemeteries is known for stories of dancing orbs and glowing headstones dating back to the 1800s.

Gallery Credit: Nate Wilde

Unsettling Things at Colorado’s Most Notoriously Haunted Cemetery

WARNING: Under no circumstances should you enter this property. By doing so you risk bodily harm and/or prosecution for trespassing on private property.

Colorado’s Central City Cemetery is not only notorious for being extremely haunted, but a recent visit saw unsettling things like vandalism, pentagrams, and a small, oddly placed building with an outhouse.

Gallery Credit: Nate Wilde