The Royal road aided Darius in maintaining control of the Persian Empire in a number of crucial ways:
Effective Communication: As a communication channel connecting the empire's various provinces and capital, the Royal Road facilitated speedy dispatch of messages, orders, and information, enabling efficient communication between the Central government in Susa and local administrators.
Rapid Troop Deployment: The Royal Road helped streamline troop movements, ensuring swift deployment of Persian soldiers wherever necessary. This was especially crucial for managing internal uprisings or dealing with external threats. Darius could promptly mobilize and direct his military forces with the aid of this road, preventing challenges to his authority and keeping the empire secure.
Centralized Governance: The Royal Road made it possible to establish centralized governance by promoting quick and direct transfer of orders, decrees, and policies from the capital to remote areas of the empire. Darius was able to enforce consistency in administration, maintain political control, and prevent conflicts or instances of disobedience by implementing uniform laws, regulations, and tax policies.
Administrative Supervision: The Royal Road enabled imperial administrators to efficiently travel to different provinces of the empire, monitoring the activities of local leaders, ensuring fiscal discipline, addressing problems, and maintaining uniformity in regional administration. This continuous monitoring helped Darius to prevent instances of corruption, ensure fairness in taxation, and enforce uniform governance across the empire.
Trade and Economic Integration: The Royal Road boosted economic integration and the development of trade routes. Merchants, traders, and caravans travelled along this road, transporting goods, crafts, and luxuries from all corners of the empire to major trading centers. The resulting commercial prosperity generated resources for the state, fostered economic growth, and contributed to overall stability.
Overall, the Royal Road enabled Darius to ensure efficient communication, maintain unity among the empire's subjects, deploy military forces where necessary, enforce centralized governance, monitor administrative activities, and facilitate trade. It played a pivotal role in the administrative and political infrastructure of the Persian Empire and contributed to the preservation of Darius' authority and the empire's stability.