'Reign' in the Bible

In the eighth month of the second year of the reign of Darius, this message from the LORD came to Berechiah's son Zechariah, the grandson of Iddo the prophet:

On the twenty-fourth day of the eleventh month (the month Shebat) in the second year of the reign of Darius, this message from the LORD came to Berechiah's son Zechariah, the grandson of Iddo the prophet:

During the fourth year of the reign of King Darius, a message from the LORD came to Zechariah on the fourth day of the ninth month Kislev.

You will run away through my mountain valley, because the valley of the mountains will extend as far as Azal. You will flee, as you fled from the earthquake during the reign of King Uzziah of Judah. And so the LORD my God will come, and all his holy ones will be accompanying you."