I'm not too sure about whether it was reintroduced in India. I'm sure Arrian mentions something about this, but I haven't read his work entirely. What I know for sure is that the sarissas were dropped in Central Asia, because they were too much of an obstacle in mountain warfare.
When the Macedonians returned to more familiar terrain, they probably reintroduced the sarissa.
When the Macedonians returned to more familiar terrain, they probably reintroduced the sarissa.
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