Imperial maps classified more than mountains and rivers. They arranged populations, languages, resources, routes, and perceived risks into forms legible to officials. Focusing on knowledge production, this account explores how explorers, surveyors, soldiers, interpreters, and local informants contributed to maps whose authority was unevenly distributed. It asks whose observations became official and whose spatial knowledge disappeared behind standardized symbols. The history reveals cartography as a collaborative yet unequal practice, shaped by technology, bureaucracy, and ambition. Readers see how measurement could convert human diversity into administrative categories with lasting political consequences.