That morning of June 28, even as Catherine was being proclaimed Autocrat of All the Russias in the Kazan Cathedral in St. Petersburg, Peter III, wearing his blue Prussian uniform, was drilling his Holstein soldiers on the parade ground at Oranienbaum. This concluded, he ordered six large carriages to carry him and his entourage to Peterhof, where, he had informed Catherine, he would celebrate his name day, the Feast of St. Peter and St. Paul. In the emperor’s party were Elizabeth Vorontsova; her uncle, Chancellor Michael Vorontsov; the Prussian ambassador, Baron von Goltz; Count Alexander Shuvalov; the elderly Field Marshal Count Münnich; and the senior senator, Prince Trubetskoy. Many of these dignitaries were accompanied by their wives, and there were also sixteen young maids of honor who served the presumed empress-to-be. This cavalcade started without the usual escort of hussars; Peter had forgotten to order it.
In high spirits, the company arrived at Peterhof at two in the afternoon. The carriages pulled up in front of the Mon Plaisir pavilion, where Catherine was supposed to be waiting to congratulate her consort on his name day. When they arrived, the doors and windows were tightly closed and no one came out to greet them. No one, in fact, was there at all except a frightened servant, who could tell them only that the empress had left early that morning and that he did not know where she had gone. Refusing to believe what he had seen and been told, Peter rushed inside the empty house, running from room to room, peeping under beds, lifting mattresses, and finding nothing except the gala dress laid out the night before for Catharine to wear at Peter’s name day celebration. Infuriated that Catherine had spoiled his moment and his day, he screamed at Vorontsova, “Didn’t I always tell you she was capable of anything?” After an hour of tumult and dismay, the chancellor, Michael Vorontsov, volunteered to go to back to St. Petersburg, where Catherine was presumed to have gone, to seek information and “speak seriously to the empress.” Alexander Shuvalov and Prince Trubetskoy offered to accompany him. At six o’clock, when they reached the city, Catherine was still there and Vorontsov made an effort to tell her that she should not be taking up arms against her husband and sovereign. Catherine’s response was to lead him onto a palace balcony and point to the cheering crowd below. “Deliver your message to them, sir,” she said. “It is they who command here. I only obey.” Vorontsov was taken to his house where, that evening, he wrote to Catherine as his “most gracious sovereign, whom the inscrutable decree of Providence has raised to the Imperial throne.” He asked to be relieved of all his offices and duties and allowed to pass the rest of his days in seclusion. Before nightfall, Alexander Shuvalov swore allegiance to Catherine.
At three in the afternoon, after these three emissaries had departed from Peterhof, Peter received the first sketchy information about the coup. A barge, traveling across the bay from the city, carried the fireworks intended for use that night in the name day celebration. The lieutenant in charge, a specialist in fireworks, told Peter that at nine that morning, when he had left the capital, there was great excitement in the barracks and the streets because of a rumor that Catherine had arrived in the city and that some of the troops had proclaimed her empress. He knew no more because, given orders to deliver fireworks to Peterhof, he had departed.