Caligula’s Bridge

The Express has a piece (for reasons unknown … but  it’s written by Matthew Dennison, whose 12 Caesars is getting reviewed all over the place) about the excesses of assorted emperors. Here’s the incipit:

IN AD 37 the new Roman Emperor Gaius, better known by the nickname Caligula, built a bridge across the sea.

It stretched three miles across the deep blue waters of the Bay of Naples at ancient Rome’s most fashionable seaside resort of Baiae.

But Caligula’s was no ordinary bridge. It was a temporary, floating structure built on wooden pontoons, a costly and impressive feat of engineering. It served a single purpose before being dismantled.

On a day of boiling heat watched by crowds of spectators, Caligula rode across the bridge. His armour glinted in the sunlight, for the 24-year-old emperor had dressed himself in the golden breastplate of the legendary Greek hero Alexander The Great.

On the following day Caligula made the journey in reverse, this time riding in a chariot, followed by soldiers of his personal guard.

It was a pointless piece of showmanship, lost on the majority of the crowd, several of whom fell drunkenly to their deaths in the sea after two days’ partying.

One historian claimed Caligula pulled the stunt to disprove a prophecy that he had no more chance of becoming emperor than of riding a horse across the Bay of Baiae.

Whatever his motives, this eccentric and expensive prank was typical of his short reign. […]

This is one of those incidents from Caligula’s life which I have long believed has been misunderstood greatly by historians — both ancient and modern — because it is usually put in the context of Caligula’s ‘madness’ and/or ‘massive ego’. Cassius Dio puts this incident in the events of the year 39 (as Barrett notes, p. 211) — connected somehow to the impending German campaign — and describes it thusly (59.17 via Lacus Curtius):

1 Gaius, however, did not care at all for that kind of triumph, as he did not consider it any great achievement to drive a chariot on dry land; on the other hand, he was eager to drive his chariot through the sea, as it were, by bridging the waters between Puteoli and Bauli. (The latter place lies directly across the bay from the city of Puteoli, at a distance of twenty-six stades.) 2 Of the ships for a bridge some were brought together there from other stations, but others were built on the spot, since the number that could be assembled there in a brief space of time was insufficient, even though all the vessels possible were got together — with the result that a very severe famine occurred in Italy, and particularly in Rome. 3 In building the bridge not merely a passageway was constructed, but also resting-places and lodging-room were built along its course, and these had running water suitable for drinking. When all was ready, he put on the breastplate of Alexander (or so he claimed), and over it a purple silk chlamys, adorned with much gold and many precious stones from India; moreover he girt on a sword, too a shield, and donned a garland of oak leaves. 4 Then he offered sacrifice to Neptune and some other gods and to envy (in order, as he put it, that no jealousy should attend him), and entered the bridge from the end at Bauli, taking with him a multitude of armed horsemen and foot-soldiers; and he dashed fiercely into Puteoli as if he were in pursuit of an enemy. 5 There he remained during the following day, as if resting from battle; then, wearing a gold-embroidered tunic, he returned in a chariot over the same bridge, being drawn by race-horses accustomed to win the most victories. A long train of what purported to be spoils followed him, including Darius, a member of the Arsacid family, who was one of the Parthians then living in Rome as hostages. 6 His friends and associates in flowered robes followed in vehicles, and then came the army and the rest of the throng, each man dressed according to his individual taste. Of course, while on such a campaign and after so magnificent a victory he had to deliver a harangue; so he ascended a platform which had likewise been erected on the ships near the centre of the bridge. 7 First he extolled himself as an undertaker of great enterprises, and then he praised the soldiers as men who had undergone great hardships and perils, mentioning in particular this achievement of theirs in crossing through the sea on foot. 8 For this he gave them money, and after that they feasted for the rest of the day and all through the night, he on the bridge, as though on an island, and they on other boats anchored round about.

Suetonius describes it very similarly, and also seems to put it in the context of 39 A.D. (19, again via Lacus Curtius):

1 Besides this, he devised a novel and unheard of kind of pageant; for he bridged the gap between Baiae and the mole at Puteoli, a distance of about thirty-six hundred paces, by bringing together merchant ships from all sides and anchoring them in a double line, afterwards a mound of earth was heaped upon them and fashioned in the manner of the Appian Way. 2 Over this bridge he rode back and forth for two successive days, the first day on a caparisoned horse, himself resplendent in a crown of oak leaves, a buckler, a sword, and a cloak of cloth of gold; on the second, in the dress of a charioteer in a car drawn by a pair of famous horses, carrying before him a boy named Dareus, one of the hostages from Parthia, and attended by the entire praetorian guard and a company of his friends in Gallic chariots. 3 I know that many have supposed that Gaius devised this kind of bridge in rivalry of Xerxes, who excited no little admiration by bridging the much narrower Hellespont; others, that it was to inspire fear in Germany and Britain, on which he had designs, by the fame of some stupendous work. But when I was a boy, I used to hear my grandfather say that the reason for the work, as revealed by the emperor’s confidential courtiers, was that Thrasyllus the astrologer had declared to Tiberius, when he was worried about his successor and inclined towards his natural grandson, that Gaius had no more chance of becoming emperor than of riding about over the gulf of Baiae with horses.

Of course, all this will likely be familiar to the sorts of folks who would visit rogueclassicism, but way back when I was doing my first Classics-related degree, lo those decades ago, and was writing my paper about Caligula’s assassination, it struck me that this might very well have been an incident that has ‘shifted’ in our sources in order to augment the ‘madness’ of Caligula. What if, instead of being something which happened prior to the departure for Germany — and the aborted invasion of Britain — it actually was a response to that famous incident. Consider how it is fragmentarily described in Dio (59.25 via Lacus Curtius):

And when he reached the ocean, as if he were going to conduct a campaign in Britain, and had drawn up all the soldiers on the beach, 2 he embarked on a trireme, and then, after putting out a little from the land, sailed back again. Next he took his seat on a lofty platform and gave the soldiers the signal as if for battle, bidding the trumpeters urge them on; then of a sudden he ordered them to gather up the shells. 3 Having secured these spoils (for he needed booty, of course, for his triumphal procession), he became greatly elated, as if he had enslaved the very ocean; and he gave his soldiers many presents. The shells he took back to Rome for the purpose of exhibiting the booty to the people there as well.

… and Suetonius (46 … Lacus Curtius again):

Finally, as if he intended to bring the war to an end, he drew up a line of battle on the shore of the Ocean, arranging his ballistas80 and other artillery; and when no one knew or could imagine what he was going to do, he suddenly bade them gather shells and fill their helmets and the folds of their gowns, calling them “spoils from the Ocean, due to the Capitol and Palatine.” As a monument of his victory he erected a lofty tower, from which lights were to shine at night to guide the course of ships, as from the Pharos.81 Then promising the soldiers a gratuity of a hundred denarii each, as if he had shown unprecedented liberality, he said, “Go your way happy; go your way rich.”

Back when I was writing my paper, the ‘party line’ on this incident was essentially that of JPVD Balsdon, whose 1934 book on Caligula suggested that the soldiers had actually refused to make the crossing (pp 90 ff) and I suspect that is the view that many still hold today. If so, it is not difficult to imagine Caligula going back to Rome and deciding that invading Britain by trireme wasn’t going to happen.  Even if they didn’t actually refuse — there seems to be only one trireme involved here; clearly not enough for an army — Caligula’s little boat ride may have been a literal pre-invasion ‘testing of the waters’ to see how rough the seas were. What if he did take inspiration from Xerxes and actually planned to build a boat bridge across the Channel to march his soldiers across? The bridge at Baiae then becomes a possible military feasibility exercise which may have had merit, especially when we hear of him tarrying for a day ‘on the other side’, given that it would probably take about a day to march across the channel on such a bridge. Of course, bridging the 20+ miles of the Channel would be a bit more involved than the two or three of the the Bay of Naples, but it seems to me it just might be the sort of thing a Caligula might think of doing after all his ‘preparations’ in Germany and environs. Something to consider, anyway …