Ötzi, Europe's oldest mummy, most likely suffered a substantial head injury before he died, according to Live Science.

The mummy is thought to have died about 5,300 years ago. He was found in 1991 by a group of hikers in the Alps.

When discovered, Ötzi was frozen and extremely well preserved. Scientists were able to put together a good picture of who the mummy was during his lifetime, he died at about the age of 45 in central Europe. Ötzi was a tattooed agriculturist, who suffered from a number of ailments including "heart disease, joint pain, tooth decay, and probably Lyme disease" before his death. Now experts think that he also suffered from a brain injury right before he died.

The ancient man was thought to have died from being struck with an arrow in the artery located on his shoulder, an undigested meal in the mummy's stomach suggests that he may not have been expecting the attack.

In 2007, researchers found black spots in the back of Ötzi's cerebrum, recent studies have shown this indicates a harsh blow to the head before death.

It's yet to be determined whether the bruising was caused by an intentional injury, such as being hit over the head, or if the "ice man" suffered the blow when he fell from the arrow piercing his shoulder.

In 2012, a different study examined the mummy's red blood cells, which were the oldest ever studied, they were able to identify a protein called fibrin. The protein is released in the blood immediately after an injury, but disappears soon after. The fact that fibrin was still present in the mummy's cells suggests that Ötzi didn't survive for long after the injury occurred.

"Proteins are the decisive players in tissues and cells, and they conduct most of the processes which take place in cells," said Andreas Tholey, a scientist at Germany's Kiel University who is working on the study. "Identification of the proteins is therefore key to understanding the functional potential of a particular tissue."

A discovery like this was found in such old tissue is extremely exciting to scientists.

"When you think that we have succeeded in identifying actual tissue changes in a human who lived over 5,000 years ago, you can begin to understand how pleased we are as scientists that we persisted with our research after many unsuccessful attempts," said Frank Maixner, a microbiologist at the European Academy of Bolzano/Bozen who is also working on the study.