Person entrusted with the responsibility:
The person entrusted with the responsibility of looking after conquered territory in the south was a provincial governor, known as a "satrap" in ancient Persia.

Responsibilities of a satrap:
- The satrap was appointed by the Persian king to govern a specific province or region.
- They were responsible for collecting taxes, maintaining order, and overseeing the general administration of the territory.
- Satraps were expected to ensure the loyalty of the local population and prevent rebellion or uprisings.
- They had the authority to enforce laws, settle disputes, and administer justice within their jurisdiction.

Relationship with the Persian king:
- Satraps were accountable to the Persian king and had to report directly to him on matters concerning their province.
- They were required to pay tribute to the king and send regular reports on the political and economic situation in their territory.
- Satraps who failed to fulfill their duties or acted against the interests of the king could be replaced or punished.

Role in maintaining Persian control:
- Satraps played a crucial role in maintaining Persian control over the vast empire by ensuring stability and order in their assigned territories.
- They often relied on local officials and advisors to help govern effectively and address the needs of the diverse population under their rule.
- Satraps were instrumental in integrating conquered lands into the Persian administrative system and promoting cultural exchange within the empire.
Overall, the position of satrap was crucial in the Persian Empire's governance structure, as these provincial governors helped to consolidate and expand the empire's power in the south and beyond.