The effort to prevent the rebuilding of the Temple was not limited to scattered local disturbances. The enemies of the returning exiles launched a prolonged, highly organized, and well-funded political campaign. This hostile endeavor spanned several changes in the Persian empire's leadership and ultimately succeeded in bringing construction to a complete halt.
The primary approach among commentators is that these adversaries actively paid off various advisors to advance their agenda. The nature of this hiring points to a deeper, more sinister strategy, suggesting an intention to employ false witnesses and corrupt counselors. Ultimately, however, God confused their efforts and silenced their deceitful claims [רב סעדיה גאון, מנחת שי]. Another perspective reveals the sheer intensity of their hatred, indicating that these enemies were willing to sacrifice their own lives if it meant successfully disrupting the Jews [רב סעדיה גאון].
The sole purpose of these hired counselors was to feed the Persian king false information, turning his mind against the Jews and ruining the leaders' plans to rebuild the Temple [מצודת דוד, רב סעדיה גאון]. This relentless campaign of political sabotage was directed primarily at the tribes of Judah and Benjamin, who formed the vast majority of those returning from the Babylonian exile. The remaining ten tribes had chosen to stay in the Assyrian exile, anticipating that another destruction would eventually occur [רב סעדיה גאון].
The combination of endless political harassment and severe economic hardship proved too much to bear. The small number of returnees were already struggling to cultivate land that had been abandoned for decades. Under the weight of these pressures, the physical work on the Temple finally ceased [ביאור שטיינזלץ].
This period of intense disruption began during the reign of Cyrus, persisted throughout the rule of his successor Ahasuerus, and only came to an end during the second year of the reign of Darius [רש״י, רב סעדיה גאון]. Regarding the exact identity of Darius, opinions vary. He is identified by some as the son of Ahasuerus [מצודת דוד], with a specific tradition noting him as the son of Queen Esther [רב סעדיה גאון]. Alternatively, others identify him as the grandson of Cyrus [רלב״ג].