How did terrain and weather affect ancient warfare?

Answer 1

Rougher terrain was favoured by armoured infantry to protect them from cavalry and vice versa. However rough terrain also made it difficult for a phalanx to maintain its tight formation, which led to the Romans developing open formations.

Very wet weather made it difficult for cavalry and impeded infantry manoeuvrering.

Other extremes of wet, dry, cold, hot each had their own deleterious effects, and led to campaigning in summer. In the earlier periods when the army was largely comprised of farmers, , campaigns were also delayed until after the harvest had been gathered in.