Julius Caesar (100 – 44 BC) completed the defeat of Gaul in 51 BC, extending Rome’s reach to the English Channel, creating the imperial foundation that launched the Roman Empire (27 BC – 395 AD).
Caesar wrote of battling the seafaring Celtic Veneti, whose fleet of superior, larger ships (with no oars) were made of heavy oak transoms fastened by long iron nails “the thickness of a thumb“. Only by slashing the halyards of the Veneti’s leather sails did he disable and defeat the enemy.
Hand-forged iron nails (10” and longer) revolutionized Roman shipbuilding (bigger warships and merchant fleets), fortified military camps (“Castra“), and siege engines. Military Engineering progressed steadily from each conquest, merging and perfecting innovations of other cultures on a scale that the world had never seen before. Size matters in world domination.
Rome’s insatiable need for iron ore demanded improved metallurgy, conquest of distant territories, and the stable administration of mines in those lands, including Spain, Portugal, Austria, Britain, Egypt and Carthage (Tunisia).
A Roman Fortress in Britain (Scotland), dating to 83 AD, was excavated in 1952-65 and found to have 750,000 iron nails buried in a pit. Distant outposts used the same heavy hardware throughout the Empire.
“For the want of a nail”. Not this kingdom.