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Map of "acceleration in the use of iron"
(i.e. not its earliest use but when iron became frequently used as weapons, farming tools, building materials, ornaments).
Northern India was earliest.
(i.e. not its earliest use but when iron became frequently used as weapons, farming tools, building materials, ornaments).
Northern India was earliest.
First militarily significant use of high-quality steel swords.
(There had to be enough good steel available.)
(There had to be enough good steel available.)
Spread of iron helmets
Great piece of data collection and presentation by @EALTurner
As can be seen from the maps, iron-making spread across sub-Saharan Africa, but they seem not to have made helmets or steel (iron alloyed with carbon) swords
