The murder of the last Severan emperor Severus Alexander and the ascension of Maximinus Thrax, a praefectus legionis of Thracian origin, to the purple, mark the epoch event of the Crisis of the 3rd century.

They found the Harzhorn pass blocked by a large number of Germans, and had to fight their way through, using their superior Roman artillery.

When one of the artifacts they unearthed turned out to be a Roman hippo sandal, they notified the Northeim county archaeologist, who is responsible for this area.

In the north–south direction, it can only be crossed on a narrow pass, which is part of an ancient trade route, and today occupied by the Bundesautobahn 7.

A coin minted under and showing the portrait of Emperor Commodus and some specific pieces of military equipment originally dated the battle to after 180 AD.

[4] Germanic tribes had crossed the Rhine and devastated the Roman countryside in 233; in 235, Maximinus Thrax led a campaign of revenge into Germania, which had been prepared by his predecessor, Severus Alexander.

The Battle at the Harzhorn, as interpreted by the artifacts found to date, now proves that the Romans went far deeper into Germania during the 3rd century than was thought possible earlier.

These campaigns mark the end of Rome trying to conquer the lands between Rhine and Elbe and make them part of the Roman empire.

In the following years, the Romans expanded their border fortifications to include parts of Germania, and shorten their lines of defense.