Without infrastructure in his kingdom, Attila built an army of versatile and nimble horsemen. Funded by enormous tributes collected from foreigners (and plunder forcibly taken from others), he could well afford to pay (and feed) his troops and their horses. The Hun bow was their decisive weapon. Attila held his domains through fear.
Using terrain as cover, until they were within arrow range, the Huns would send arrow showers at unspecified targets. They used the sword as well, for close combat.
Historians believe that Hunnic boys were taught to use a sword by the age of five. It was said (and noted by Edward Gibbon in The Decline and Fall of the Roman Empire) that Attila was presented with the sword of the god Mars (which he wielded with brutal ferocity).
Even after his people were given a homeland, Attila remained a nomadic warrior. Having plundered towns and cities in the Eastern Empire, the King of the Huns decided to go west, to Gaul. It would be another winning journey, but it culminated in a battle which Attila lost.
It is believed Attila’s headquarters were located at, or near, Aquincum, a town Rome founded on the west bank of the Danube River. That city of hills, subsequently called Buda, is now the left-bank side of Budapest. (Buda, and the flat-lands city of Pest, located on the eastern bank of the Danube, were combined into one city - Budapest - in the 19th century.)
Attila’s likely route west (from his headquarters to the Seine, among other places) is depicted in William R. Shepherd’s 1911 Historical Atlas. Let’s trace his path to virtually visit some of the towns he captured or besieged.