The Achaemenid Empire, topping the list, utilized the 'Royal Road' not just for logistics, but as the heartbeat of a massive bureaucratic network. The most remarkable discovery, the Persepolis Fortification Tablets, consists of over 30,000 clay documents detailing everything from grain rations and wages to livestock transfers. While the Roman Empire’s records lean heavily toward law and narrative, the Achaemenid archives functioned like a modern enterprise-grade ERP system, precise down to the gram. Spanning two decades (509–494 BCE), the level of detail allows historians 2,500 years later to reconstruct the daily diet of workers. This 'administrative obsession' puts the empire far ahead of contemporary Greek city-states in terms of both archival integrity and economic transparency.