According to Stanford university both the Han chinese and the
Roman Empire had roughly the same population...
Furthermore:
Annual metal output in metric tons
Roman Empire: Iron 82,500... Copper 15.000... Lead 80.000...
Silver 200
Han China: Iron 5.000... Copper Negligible...Lead
Negligible...1
Which in turn means that the Han army couldnt possible equip
their huge armies at the same standards of the roman army.
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Roads ( important to battles ) --- Rome: 250,000 miles (400,000
km) of roads, including more than 50,000 miles (80,500 km) of
paved roads.
Han China: The Han road system, mostly unpaved, was 22,000
miles