There are a lot of things that they don’t exactly teach us in school when it comes to history lessons of all kinds, including state and local history. However, those of us with a morbid curiosity streak might go looking for the darker side of our home-state history, and boy, have we found it. Did you know that in the summer of 1936, an Indiana man went on a murderous rampage triggered by jealousy that was easily one of the most gruesome incidents in American history (up to that point, anyway)? It happened, and the whole story of these murders in Indiana is to-the-bone chilling.

The FBI defines a “mass murder” as the killing of more than four people, in close proximity, during the same time period, i.e., there is no “cooling-off” period between each murder.

Alejandro Forero Cuervo/Flickr They define a “spree killer” as someone who kills two or more people in two or more locations during a short time period. Given these definitions, the man who would commit one of the most gruesome crimes in the annals of American History could be defined as both.

In July 1936, an Indiana man by the name of Celestino Gonzalez took his family out for a beach day on an incredibly hot 107-degree day.

Jennifer Kirkland/Flickr It was the fourth consecutive day of sweltering temperatures above 100 degrees, and as a result, everyone was already rather miserable. Celestino, however, was seething. He had discovered love letters exchanged between his wife and a man who had previously lived with them, and that day would be the last time the Gonzalez family would ever have an outing together.

Once the family had returned home for the evening and everyone else had gone to bed, Gonzalez waited to make sure they were soundly asleep before beginning his rampage.

Thomas Berg/Flickr First, he went into the room where his two teenaged daughters - Helen, 14, and Juana, 16 - slept, and killed them both with several blows from an ax. There was extensive evidence that they had tried to fight him, but it was no use. The girls were the first to go, and their rage-filled father had only just started.

Seven-year-old Jose awoke when he heard the scuffle from the first two murders, and ran to his mother’s room, panicking.

D.Laniel photo/Flickr His mother, Maria, 31, fled to the kitchen, where Gonzalez caught up with her. He killed her with three blows to the head before moving to the bedroom where Jose hid. Jose, the youngest of the six Gonzalez children, would die next.

Gonzalez then moved into the next room, where his other three sons - Phillip, 8, Tino, 11, and Genaro, 13 - slept.

Patrick Brosset/Flickr It is not known if they were aware of what was happening or not. However, given the brutality of the struggle between their father and their youngest brother, as well as their mother, it is likely safe to assume they were quite aware and could do nothing to stop it or change their fates. Gonzalez had made up his mind hours before.

In Spanish, he scrawled out several notes before settling on one that read, in part: “…I have decided to quit this house of Gonzalez. With pain in my heart, I give death to all my sons.”

Greg Walters/Flickr Gonzalez sat alone in the dark, silent living room, the bodies of his family all around him. He waited until dawn when he set out to the steel plant where the previous boarder worked.

He confronted the man in the locker room of the facility before shooting him four times in the chest.

Kevin King/Flickr He then turned the gun on himself.

The village of Indiana Harbor was stunned.

moominsean/Flickr Homicide and violent crimes weren’t something that often made their way into the mainstream back then, but the terrifying story of the family man who destroyed his entire family before going on to kill another man and then himself spread far and wide. Up until this incident, familicide was an unheard-of travesty. The shocked people of Indiana Harbor learned in the worst way just how dark human nature can be.

Craving more Hoosier-State horror stories? Give this article a look for more of some of the most notorious crimes to ever be committed in Indiana.

Alejandro Forero Cuervo/Flickr

They define a “spree killer” as someone who kills two or more people in two or more locations during a short time period. Given these definitions, the man who would commit one of the most gruesome crimes in the annals of American History could be defined as both.

Jennifer Kirkland/Flickr

It was the fourth consecutive day of sweltering temperatures above 100 degrees, and as a result, everyone was already rather miserable. Celestino, however, was seething. He had discovered love letters exchanged between his wife and a man who had previously lived with them, and that day would be the last time the Gonzalez family would ever have an outing together.

Thomas Berg/Flickr

First, he went into the room where his two teenaged daughters - Helen, 14, and Juana, 16 - slept, and killed them both with several blows from an ax. There was extensive evidence that they had tried to fight him, but it was no use. The girls were the first to go, and their rage-filled father had only just started.

D.Laniel photo/Flickr

His mother, Maria, 31, fled to the kitchen, where Gonzalez caught up with her. He killed her with three blows to the head before moving to the bedroom where Jose hid. Jose, the youngest of the six Gonzalez children, would die next.

Patrick Brosset/Flickr

It is not known if they were aware of what was happening or not. However, given the brutality of the struggle between their father and their youngest brother, as well as their mother, it is likely safe to assume they were quite aware and could do nothing to stop it or change their fates. Gonzalez had made up his mind hours before.

Greg Walters/Flickr

Gonzalez sat alone in the dark, silent living room, the bodies of his family all around him. He waited until dawn when he set out to the steel plant where the previous boarder worked.

Kevin King/Flickr

He then turned the gun on himself.

moominsean/Flickr

Homicide and violent crimes weren’t something that often made their way into the mainstream back then, but the terrifying story of the family man who destroyed his entire family before going on to kill another man and then himself spread far and wide. Up until this incident, familicide was an unheard-of travesty. The shocked people of Indiana Harbor learned in the worst way just how dark human nature can be.

Had you ever heard of this horrifying case of familicide?

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