Technically, Nabonidus was still the king of Babylon when the city fell to the Persians, and he outlived Belshazzar. However, he had been absent from the city during most of his reign, preferring to live in the rich desert oasis of Tayma (“Tema” in Jer. 25:23) in Northwest Arabia. It was the center of worship for Sin, the moon god. There he built a royal complex, which has recently been excavated by archeologists.

The priests of Marduk in Babylon complained of his apostasy, much like the prophets of Israel had denounced the rulers of Judah and Israel for their apostasy from Yahweh. Nabonidus was considered a royal anomaly in most of the Babylonian records. The Nabonidus Cylinder refers to Sin, the moon god, as “Sin, king of the gods of heaven and the netherworld, without whom no city or country can be founded.”

Belshazzar, the prince, ruled many years on behalf of Nabonidus. But when the Persian army approached Babylon, Nabonidus returned to the throne, deposing Belshazzar and some senior administrators—perhaps for their inability to stop the advance of the Persian army. According to the Nabonidus Chronicle, he also began gathering the statues of gods from various cities, perhaps intending to protect them within the walls of Babylon. However, this was viewed as offensive to the gods, and Cyrus used this as a propaganda ploy to turn cities against Nabonidus.

The Cyrus Cylinder tells us,

“As for the gods of Sumer and Akkad which Nabonidus, to the wrath of the Lord of the gods, brought to Babylon, at the command of the great Lord Marduk, I [Cyrus] caused them to dwell in peace in their sanctuaries, (in) pleasing dwellings.”

As the Persian army drew nearer, Nabonidus led the Babylonian army to meet him. Cyrus defeated Nabonidus at Opis, and Nabonidus fled to nearby Borsippa. No doubt, word came to Belshazzar that his father had been defeated (and possibly killed or captured). This would have left Belshazzar as the full King of Babylon. Up to that time, he had reigned only as a co-regent under his father.

In fact, this may have been the reason for the celebration in Dan. 5:1 on the night that Cyrus actually took Babylon.

¹ Belshazzar the king held a great feast for a thousand of his nobles, and he was drinking wine in the presence of the thousand.

It was only a short time between the battle of Opis and the taking of Babylon when Belshazzar was killed. The Cyrus Cylinder says that the people opened their gates for Cyrus and greeted him as a liberator. This suggests that the powerful priests of Marduk, who hated Nabonidus for his apostasy from Marduk, opened the gates of the city along the Euphrates—or left them open—to allow Cyrus’ troops to enter the city without a battle.

When the city was secure, Cyrus turned toward Borsippa to capture the defeated king, but Nabonidus surrendered to him voluntarily. So Cyrus allowed Nabonidus to retire in Carmania and to live out his days in peace.

Cyrus then returned the gods to their own home towns. According to The New World Encyclopedia, the Babylonian Chronicles tell us, “The gods of Akkad which Nabonidus had made come down to Babylon, were returned to their sacred cities.” By the same policy of religious freedom, Cyrus also issued a decree allowing the people of Judah to return to Jerusalem and to rebuild their temple.

The Projects of Queen Nitocris

Queen Nitocris, the wife of Nabonidus, was the mother of Belshazzar (Dan. 5:1). On the night Babylon fell, when the hand wrote on the palace wall, it was this queen who remembered the old prophet Daniel and pulled him out of retirement to interpret the dream (Dan.5:10-12).

Years earlier, Queen Nitocris wanted to build a bridge over the Euphrates to connect the two halves of Babylon. Up to that time, the people had to use boats to ferry the people across the river. So first she had her workmen dig a huge basin just north of the city that was 47 miles in circumference. At the same time she prepared large stones for the bridge. When all was ready, a canal was dug from the river to the basin, diverting the river. This reduced the flow of the river and allowed the workmen to set the stones in the dry river bed to build the bridge over the Euphrates. (See Herodotus, The Histories, book 1, Par. 186.)

Nitocris took note of the rise of the Medes many years earlier, and so she embarked on a project to fortify the city along the Euphrates. The river had flowed swiftly in a rather straight line through the city, but she slowed down its flow by redirecting the riverbed so that it included many twists and turns. Then she lined the river with stones. Thus, an invasion by ship would prove to be very difficult, as all the bends in the river would require their full attention.

Taking Babylon

Originally, Cyrus had intended to attack Babylon in 538 B.C. However, while crossing the Gyndes River, something happened which caused him to waste the entire summer of that year. Herodotus tells us the story:

“On his march to Babylon, Cyrus came to the river Gyndes which rises in the Matienian mountains, runs through the country of the Dardanes, and then joins the Tigris which passes the city of Opis and flows into the Persian Gulf. Cyrus was preparing to cross this river, for which boats were needed, when one of his sacred white horses, a high-spirited creature, entered the water and attempted to swim across but was swept under by the rapid current and carried away. Cyrus was so furious with the river for daring to do such a thing, that he swore he would punish it by making it so weak that even a woman could get over in future without difficulty and without wetting her knees. He held up his march against Babylon, divided his army into two parts, marked out on each side of the river a hundred and eighty channels running off from it in various directions, and ordered his men to set to work and dig. Having a vast number of hands employed, he managed to finish the job, but only at the cost of the whole summer wasted. Then, having punished the Gyndes by splitting it into three hundred sixty separate channels, Cyrus, at the beginning of the following spring, resumed his march to Babylon.” [Par. 117]

Cyrus wasted the summer of 538 B.C. taking revenge on the river, but by this time his troops were well experienced in the art of ditch digging. The next spring he defeated Nabonidus at the battle at Opis, and then Sippar surrendered without a fight.  Cyrus then marched on Babylon itself. But Babylon’s walls were impenetrable, and the city had been stocked with enough food to last many years. Water, of course, was no problem, as the Euphrates flowed through it. Herodotus continues,

“The siege dragged on, no progress was made, and Cyrus was beginning to despair of success. Then somebody suggested or he himself thought up the following plan: he stationed part of his force at the point where the Euphrates flows into the city and another contingent at the opposite end where it flows out, with orders to both [army divisions] to force an entrance along the river-bed as soon as they saw that the water was shallow enough. Then, taking with him all his non-combatant troops, he withdrew to the spot where Nitocris had excavated the lake (which was then a marsh) and in this way [reopening the canal] so greatly reduced the depth of water in the actual bed of the river that it became fordable, and the Persian army, which had been left at Babylon for the purpose, entered the river, now only deep enough to reach about the middle of a man’s thigh, and, making their way along it, got into the town. . . [Par. 191]

The Babylonians themselves say that owing to the great size of the city the outskirts were captured without the people in the centre knowing anything about it; there was a festival going on, and they continued to dance and enjoy themselves, until they learned the news the hard way. That, then, is the story of the first capture of Babylon.” [Par. 191]

Very little of this history is recorded in Daniel’s account of the fall of Babylon. The prophet was concerned only with the revelation of God through the handwriting on the wall. As for us, our main concern is how the overthrow of Babylon in Daniel 5 relates directly to the fall of Mystery Babylon in our time.

Jeremiah’s Hidden Book of Prophecy

When the Euphrates was diverted and the Persian troops marched through the dry riverbed into Babylon, they did not know that they were fulfilling prophecies of Jeremiah that had been spoken and placed in the river many years earlier. This is the book that Jeremiah wrote, sending Seraiah as his agent to the city of Babylon, where he was to cast the book into the river until it should be discovered by the Persian army.

The book forms part of the biblical book of Jeremiah itself, beginning in Jer. 50:1 and ending in Jer. 51:58. We then read in the next verses what Jeremiah did with this book. Jer. 51:59 says,

⁵⁹ The message which Jeremiah the prophet commanded Seraiah the son of Neriah, the grandson of Mahseiah, when he went with Zedekiah the king of Judah to Babylon in the fourth year of his reign. (Now Seraiah was quartermaster.)

Seraiah, being an official in Zedekiah’s government (“quarter-master”), visited Babylon in 593 B.C., accompanying King Zedekiah. It was not unusual for vassal kings to visit their masters, and in this case, Zedekiah probably had to reassure Nebuchadnezzar that he would not revolt against him. The quartermaster's duty was to prepare the camp each night for the king and his guards. This special trip is not recorded elsewhere, and it would have gone unnoticed except that Jeremiah had a special mission for Seraiah, the quartermaster.

This Seraiah was the brother of Baruch, Jeremiah’s scribe and companion. Baruch and Seraiah were both sons of Neriah (Jer. 32:12). This Seraiah is to be distinguished from Seraiah the son of Azriel who tried to arrest both the prophet and his scribe in Jer. 36:26, from Seraiah the son of Tanhumeth in Jer. 40:8, and from Seraiah the high priest in Jer. 52:24. The high priest, four other temple officials, and the advisers of Zedekiah, were brought captive to Babylon in 586 B.C. after the destruction of Jerusalem, and King Nebuchadnezzar sentenced them to death (Jer. 52:26, 27).

But Seraiah the quartermaster, the son of Neriah, went to Babylon  in the fourth year of Zedekiah (593 B.C.). Jeremiah gave him a special prophetic mission. Jer. 51:60-64 says,

⁶⁰ So Jeremiah wrote in a single scroll all the calamity which would come upon Babylon, that is, all these words which have been written concerning Babylon. ⁶¹ Then Jeremiah said to Seraiah, “As soon as you come to Babylon, then see that you read all these words aloud, ⁶² and say, ‘Thou, O Lord, hast promised concerning this place to cut it off so that there will be nothing dwelling in it, whether man or beast, but it will be a perpetual desolation.’ ⁶³ And it will come about as soon as you finish reading this scroll, you will tie a stone to it and throw it into the middle of the Euphrates, and say, ⁶⁴, ‘Just so shall Babylon sink down and not rise again, because of the calamity that I am going to bring upon her; and they will become exhausted’.” Thus far are the words of Jeremiah.

We see here that as soon as Seraiah arrived at Babylon, he was to read the scroll as a prophetic decree against the city and then cast it into the Euphrates. No doubt he first put it into a jar and sealed it so that the words would not be obliterated by the water. This was the place where the troops of Cyrus were destined to pass on the night that they took Babylon. When the river dried up, the troops walked along the dry (or muddy) river bed and no doubt stumbled across the jar containing Jeremiah’s prophecy about the fall of Babylon. I have no doubt that this letter was taken directly to General Gobryas who was leading the troops, and that he sent it to Cyrus himself.

Perhaps Cyrus investigated this prophecy and discovered that it was written by a prophet in Jerusalem many years earlier. Perhaps this impressed him and was part of his motivation to allow the people of Judah to return to their old land and to rebuild Jerusalem.