In 538 BCE, Cyrus the Great of the Achaemenid Empire conquered Babylon, incorporating it into his empire. His issuance of a proclamation, the Edict of Cyrus, granted religious freedom to those under Babylonian rule. This enabled Jewish exiles in Babylon, including 50,000 Judeans led by Zerubabel, to return to Judah and rebuild Jerusalem's Temple, completed circa 515 BCE.^[80] Additionally, in 456 BCE, another group of 5,000, led by Ezra and Nehemiah, returned; the former was tasked by the Persian king to enforce religious rules, while the latter was appointed governor with a mission to restore the city's walls.^[81] Yehud, as the region was known, remained an Achaemenid province until 332 BCE.

The Torah's final text, corresponding to the first five books of the Bible, is believed to have been compiled during the Persian period (around 450–350 BCE), through the editing and unification of earlier texts.^[82] The returning Israelites adopted an Aramaic script from Babylon, now the modern Hebrew script, and the Hebrew calendar, resembling the Babylonian calendar, likely dates from this period.^[83]

The Bible recounts tension between the returnees, the First Temple period's elite^[84], and those who stayed in Judah.^[85] The returnees, possibly supported by the Persian monarchy, might have become significant landowners, to the detriment of those who had continued to work the land in Judah. Their opposition to the Second Temple might reflect fears of losing land rights due to exclusion from the cult.^[84] Judah effectively became a theocracy, led by hereditary High Priests^[86] and a Persian-appointed, often Jewish, governor responsible for maintaining order and ensuring tribute payments.^{[87 ]}Significantly, a Judean military garrison was stationed by the Persians on Elephantine Island near Aswan in Egypt.