Berlin - A rediscovery of a Roman battlefield studded with old weapons in Germany has excited archaeologists this week and thrown new light on a myth-shrouded conflict between Rome and its neighbours.

In the 19th century, German historians rejected the image of their ancestors as squabbling barbarians and honed a new picture of plucky Teutonic tribes who united to repel the invading legions of Rome.

Ever since, German schoolchildren have been taught that Germany was mostly free of the Roman yoke, and were told to use the neutral term "Migration of the Peoples" for the later Germanic invasion of the crumbling empire.

The Dutch have similarly honoured the Batavi, a Germanic tribe in what is now the Netherlands, who initially cooperated with the empire, then fought it.

The discovery of the battlefield, with all the signs of a successful Roman assault on a hilltop redoubt by cavalry and infantry, has disturbed that picture because of its location: 250 kilometres deep in Teutonic territory.

The Roman column even included early cannon or ballistae: their iron projectiles, which were fired by rope springs, were still impacted in the hill.

Amateurs with metal detectors patiently recorded the direction of impact and location, unlike ordinary treasure hunters who often rip artefacts out of the ground and ruin the important evidence of where and how it lay.

Archaeologists were able to establish the Romans attacked the Harzhorn Hill from the north.

Archaeologist Guenther Moosbauer said the battle is not recorded in any surviving history book, but fits in with accounts of an expedition in the year 235 AD under Emperor Maximinus Thrax.

Two treasure hunters found pieces of iron in 2000 and showed them to a district archaeologist, Petra Loenne, who recognized them as "hippo-sandals," a kind of Roman horseshoe. She then found pieces of a Roman axe.

So far 600 artefacts have been found in a now wooded area 1,500 by 300 metres, including buttons, wheel hubs, harness parts and a worn coin minted in the 180-192 reign of Emperor Commodus.

The site of the Teutonic redoubt can by identified by where the ballista warheads and arrows hit.

Loenne says it is a uniquely well-preserved document of a Roman-era battle. The archaeologists think the Romans suffered minor losses, wiped out the redoubt then moved on quickly to stay out of danger.

Why local Teutons did not later plunder the valuable metal from the battle site remains a mystery.

The implication of the discovery, close to the A7 motorway on the west flank of the mineral-rich Harz mountain range, is that Roman punitive expeditions could indeed march into Teutonic territory at will.

The Romans said that they did not expand the Empire east and north of the Rhine river because the region was not worth having: cold, damp and inhabited by hairy savages.

That explanation has always seemed ridiculous to proud Germans, but a historian, Alexander Demandt, gently suggested in the weekly newsmagazine Der Spiegel this week that it might be true.

Spiegel's cover story, entitled Birth of the Germans, celebrated Hermann, a Teutonic prince who crushed a Roman army in the Battle of the Teutoburg Forest in 9 AD and is now celebrated there by a 54- metre-high statue.

"Heroes are a phenomenon of interpretation," Demandt said. "Our 19th century bowed down before the Teutons." Even the Marxists venerated Hermann as a freedom fighter.

German commentators say Germany may now have to rewrite its history after the battlefield find.

The south-west of Germany and the Netherlands have traditionally taken a milder view of their former Italian overlords. That region has many remains of magnificent Roman towns, roads and country estates.

This week a museum at Xanten, near the Dutch border, unveiled an extraordinary cross-cultural helmet.

The head-dress, a replica based on several rather tatty originals dug out of the soil, is made of tightly plaited horsehair and would have protected its horseman wearer's head and neck from cuts and blows in battle.

Such helmets were worn by the Batavi, a tribe that provided feared auxiliary forces for the Roman Army, restorer Frank Willer of the Rhine Museum in Bonn said.

High on horseback and with his metal visor drawn over his face, a Batavi cavalryman would have looked as spooky as some of the space warriors in the Star Wars movies.

Scholars at Xanten Archaelogical Park, which commissioned the reconstruction for its replica Roman town, said it was clearly a feature of Roman psychological warfare to look scary.

Willer said each helmet took 200 hours to make and was tailored to its wearer.

Unlike Hermann and his people, the Batavi were "friendly" Teutonic barbarians who cooperated with Rome, sold their produce at Roman markets and served the Romans as mercenaries.

Batavi helmets suddenly went out of fashion when the Batavi rebelled against Rome and were slaughtered in a bloody northern war in the year 69 AD.

But in a curious sign of how ideas cross between cultures, and even the Romans were inspired by Germanic style, the helmets came back a century later in metallic form.

Later Roman helmets throughout the Empire were embossed with plaits clearly inspired by the Batavi style. (dpa)