After Louis‘ execution, Marie Antoinette‘s fate became a central question of the National Convention. While some advocated her death, others proposed exchanging her for French prisoners of war or for a ransom from the Holy Roman Emperor. In April 1793, during the Reign of Terror, a Committee of Public Safety dominated by Robespierre was formed, and men such as Jacques Hébert began to call for Marie-Antoinette’s trial. By the end of May, the Girondins had been chased from power. Calls were also made to “retrain” the eight-year old Louis XVII, to make him pliant to revolutionary ideas. To carry this out, Louis Charles was separated from his mother on 3 July after a struggle during which his mother fought in vain to retain her son, who was handed over to Antoine Simon, a cobbler and representative of the Paris Commune. Until her removal from the Temple, Marie Antoinette spent hours trying to catch a glimpse of her son, who, within weeks, had been made to turn against her.
On the night of 1 August Marie Antoinette was transferred from the Temple to an isolated cell in the Conciergerie as ‘Prisoner n° 280‘. This was the most difficult period of her captivity. She was under constant surveillance, with no privacy. The “Carnation Plot” (Le complot de l’œillet), an attempt to help her escape at the end of August, was foiled due to the inability to corrupt all the guards.
Marie Antoinette was tried by the Revolutionary Tribunal on 14 October 1793. Some historians believe the outcome of the trial had been decided in advance by the Committee of Public Safety around the time the Carnation Plot was uncovered. She and her lawyers were given less than one day to prepare her defense. Among the accusations, many previously published in the libelles, were: orchestrating orgies in Versailles, sending millions of livres of treasury money to Austria, planning the massacre of the gardes françaises (National Guards) in 1792, declaring her son to be the new king of France, and incest, a charge made by her son Louis Charles, pressured into doing so by the radical elements who controlled him. This last accusation drew an emotional response from Marie Antoinette, who refused to respond to this charge, instead appealing to all mothers present in the room; their reaction comforted her, since these women were not otherwise sympathetic to her.
Early on 16 October, Marie Antoinette was declared guilty of the three main charges against her: depletion of the national treasury, conspiracy against the internal and external security of the State, and high treason because of her intelligence activities in the interest of the enemy; the latter charge alone was enough to condemn her to death. At worst, she and her lawyers had expected life imprisonment. In the hours left to her, she composed a letter to her sister-in-law, Madame Élisabeth, affirming her clear conscience, her Catholic faith, and her love and concern for her children. The letter did never reach Élisabeth. Preparing for her execution, she had to change clothes in front of her guards. She put on a plain white dress, white being the color worn by widowed queens of France. Her hair was shorn, her hands bound painfully behind her back and she was put on a rope leash. Unlike her husband, who had been taken to his execution in a carriage (carrosse), she had to sit in an open cart (charrette) for the hour it took to convey her from the Conciergerie via the rue Saint-Honoré thoroughfare to reach the guillotine erected in the Place de la Révolution, (the present-day Place de la Concorde). She maintained her composure, despite the insults of the jeering crowd. A constitutional priest was assigned to her to hear her final confession. He sat by her in the cart, but she ignored him all the way to the scaffold.
Marie Antoinette was guillotined at 12:15 p.m. on 16 October 1793. Her last words are recorded as, “Pardonnez-moi, monsieur. Je ne l’ai pas fait exprès.” or “Pardon me, sir, I did not do it on purpose.”, after accidentally stepping on her executioner’s shoe. Her head was one of those that Marie Tussaud was employed to make death masks of. Her body was thrown into an unmarked grave in the Madeleine cemetery located close by in rue d’Anjou. Because its capacity was exhausted the cemetery was closed the following year, on 25 March 1794.
Both Marie Antoinette’s and Louis XVI‘s bodies were exhumed on 18 January 1815, during the Bourbon Restoration, when the comte de Provence ascended the newly reestablished throne as Louis XVIII, King of France and of Navarre. Christian burial of the royal remains took place three days later, on 21 January, in the necropolis of French kings at the Basilica of St Denis.