When British builders stumbled upon the remains of a 2,500-year-old Iron Age burial site in Pocklington, East Yorkshire, they didn't know what they accidentally unearthed. The discovery included human skeletons, weapons and artifacts. The analysis revealed that one of the human skeletons belongs to an ancient warrior king.

The burial site belonged to the Arras culture who lived during the Middle Iron Age. This population is believed to have had unique burial practices.

The remains of the youthful warrior king was pierced with a spear to "release his spirit," researchers say. His sword was found next to his skeleton.

The accidental discovery was hailed as one of the biggest and most important Iron Age Europe discoveries in almost 40 years. Archaeologist Paula Ware said that the warrior king was placed in a box in a barrow, or burial chamber, in a crouching position.

Ware theorized the warrior king was between the ages of 17 and 23 at the time of his death. Four spears were found along the warrior king's spine and one in his groin.

"He was possibly a warrior - someone who had achieved status within society. In the Iron Age we can definitely see this ritual of death was so important. It wasn't just a simple thing," added Ware, who is also the managing director of MAP Archaeological Practice, one of the leading heritage consultants and archaeological contractors in northern England.

The researchers also found the remains of a second warrior, whose skeleton was placed on his shield. Ware referred to this as a "shield burial" and considered it a unique find. It was the first documented discovery of a shield burial in Britain.

The Iron Age burial site revealed several human skeletons inside wicker baskets or on top of organic beds. Among the human skeleton finds, three warrior barrows stood out. Instead of the typical square barrows, these three warriors were placed in round graves.

The researchers started to see a pattern emerge. It seemed that the round graves were reserved for important members of the village. The site excavation yielded 75 graves during their year-long study. The researchers expect to find at least two more graves.