Ancient Roman 'spike defenses' developed by Julius Caesar discovered in Germany

Julius Caesar is known as one of history's greatest strategists and tacticians, and researchers in Germany might have uncovered the best-preserved example of a defensive structure he pioneered more than 2,000 years ago.

The so-called 'spike defense' was also known as 'Roman barbed wire', and was written about by Julius Caesar in his Gallic Wars, which is Caesar's recounting of his military campaigns in modern-day France and Germany. The defense is a series of sharpened tree branches embedded at the bottom of a covered ditch around a Roman fortification. Enemy forces who attempted to cross the ditch would fall through and impale themselves on the spikes below.

Now, according to Live Science, a student team from Goethe University in Frankfurt uncovered the oldest known examples of the defense along the old Roman frontier at a place between the modern-day German cities of Bonn and Mainz.

The site is a little over a mile away from an already-known site of an ancient Roman fort, first uncovered in 2016. The new find is located at Blöskopf Hill, which contains the first preserved examples of the wooden spike defense yet discovered.

Alongside the spike a Roman coin dated to 42 CE was discovered, putting the spike around 100 years after Julius Caesar, but also earlier than later Roman fortifications along the empire's northern border.

Camp might have been protecting an ancient Roman silver mine

The site appears to be a fortified camp built to defend a nascent silver mining operation being carried out by the Romans in the area.

In the area, previous digs have uncovered a major Roman fort, though one with few permanent structures, along with silver ore, metal slag, and evidence of a large contingent of soldiers.

A clue to the purpose of the camp comes from the Roman historian Tacitus, who wrote that a Roman governor Curtius Rufus tried to dig for silver in the area around 47 CE, but was ultimately unsuccessful. There was, in fact, silver in the area where the Romans were digging, but it was deeper than they appear to have gone.

The silver mining operation would also explain the defenses and the nearby garrison of troops. Given the potentially lucrative find, a surprise raid by hostile locals wouldn't be out of the question.