Final answer:
Nehemiah, cup-bearer to King Artaxerxes I of Persia, rebuilt the wall of Jerusalem as its governor, securing the city after the Babylonian conquest.
Step-by-step explanation:
The cup-bearer to a foreign king who rebuilt the wall of Jerusalem was Nehemiah. He served under King Artaxerxes I of Persia and later took on the role of governor in the province of Judah where he oversaw the reconstruction of Jerusalem's walls, which were in ruins following the Babylonian conquest. His dedication to the task and his leadership were instrumental in the successful completion of the walls, providing security and stability for the people of Jerusalem.