Living through history is unnerving. As an unknown number of visitors descend upon the city—a million strong? Five million? A few hundred thousand?—the urban core becomes an armed camp, the river becomes a defensive wall, and mobs cross the bridges on foot. After clambering over monuments, some folks shack up with locals who’ve turned into hostelers, a few of them are bound to be scammed, and the authorities scramble to react to an influx of tourists whose movements are decentralized and largely spontaneous.

The medieval Romans may not have draped patriotic bunting across the facades of their buildings, but 710 years ago, they braced for unprecedented crowds. In late 1299, apparently with no official prompting, pilgrims began streaming into Rome, driven by the widespread belief that the year ahead offered special blessings to those who visited the graves of St. Peter and St. Paul.

Here’s Paul Hetherington on what became the Church’s first Jubilee Year:

The word spread like wildfire through Europe, and even by New Year’s Eve of 1299 a great crowd had assembled at St. Peter’s to greet the opening of the Jubilee Year at midnight. From then on, the crowds flocked to Rome from all over the known world. No one had ever experienced anything like it before. The crowds were so massive that the papal police had to institute a keep-right system for all the crowds crossing the bridge on foot that led over the Tiber to St. Peter’s . . .

The spontaneity and scale of the Jubilee took everyone by surprise. Even the pope, Boniface VIII, seems to have been nonplussed by it, and only issued the decree authorizing it late in February 1300. The various estimates made by contemporaries of the numbers that visited Rome vary so wildly that none can be regarded as trustworthy, but it was probably somewhere between one and two million.

Hetherington translates an eyewitness account by chronicler William Ventura, who visited Rome at the end of 1300:

It was a marvellous thing how many went to Rome in that year, for I was there and stayed for 15 days. Of bread, wine, meat, fish, and fodder for horses there was, but all at special prices…Leaving Rome on Christmas Eve I saw a great crowd that I was not able to number; there was a report among the Romans that there were then more than two million men and women in the city. Several times I saw men and women trampled under the feet of others, and even I was in the same danger, only just escaping on several occasions. The Pope received an untold amount of money from them, as day and night two priests stood at the altar of St. Paul’s holding rakes in their hands, raking in infinite money…And I, William, was there and earned fifty years and more of indulgence. Each hundred years it will be the same.

Like all pilgrimages, Tuesday’s inauguration and its attendant brouhaha will be a pageant of honor, corruption, villainy, and holiness, so if you’re in town, and if your peregrinations take you to Connecticut Avenue, look for me. Adapting the experience of William Ventura to Washington tradition, I’ll be pacing the sidewalk with ful devout corage and wielding my new favorite medieval-themed religious implement, the money rake. Commit yourself to change—or simply fling cash. I promise it will go someplace deserving. Weary pilgrim, have faith in me: I wol yow nat deceyve.