Maria de Roux was born in 1821 in Switzerland. She moved to England and found work as a lady's maid. In 1846, on a trip to the French port of Boulogne with her employer, she met Patrick O'Connor, a 50 year old Irishman, who was a customs officer in Wapping, in the London docks, and a heavy drinker. Maria was also seeing Frederick George Manning, who worked as a guard on the Great Western Railway. Both men proposed, and she chose Manning, who was nearer her own age: the couple married in St James' Church, Piccadilly, in May 1847. They set up home in Miniver Place, in Bermondsey in the East End.
Maria was still in contact with O'Connor and was probably having an affair with him, with the apparent acquiescence of Frederick. O'Connor even dined with them occasionally.
On the 8th of August 1849, having bought some quicklime and a shovel, the Mannings invited Mr. O'Connor to dinner. He came with a friend. So Maria invited him again for the next day, telling him to come alone. When he arrived, she suggested he might want to wash his hands before dinner and as he stood at the sink to do so, she shot him in the head with a pistol.
The bullet wound failed to kill him, but Frederick finished him off by bashing his head with a crowbar. The two conspirators buried the body in a grave below the kitchen flagstones -- which they'd already dug -- covering it with plenty of quicklime.
The following day Maria went to O'Connor's lodgings and systematically went through his belongings, taking everything of value including his share certificates. She paid a further visit the following day to see if there was anything she had missed.
Two days later two of O'Connor's colleagues came to the Manning's house looking for him. Maria said he'd eaten with them on the 8th but denied having seen him since. Maria and Frederick were rattled and they decided to leave London immediately. Maria caught a train to Edinburgh. Frederick went to Jersey.
O'Connor's friends had, by this time, reported him missing to the police and expressed their suspicions about the Mannings. The police searched the house, lifted the flagstones, and found the body. Maria was tracked down to Edinburgh, where she had aroused suspicions by trying to sell some of O'Connors's shares. Frederick was arrested a week later in Jersey where he had been spotted by a man who had known him in London and who had read about the murder in the papers.
The trial took place at the Old Bailey 25th of October. Their respective lawyers tried to blame the other for the killing. It took the jury forty-five minutes to find them both guilty.
Maria screamed at the jury, "You have treated me like a wild beast of the forest." She continued to rave at the judge as he tried to pass sentence of death upon her.
As she waited for execution, Maria attempted suicide; she also wrote to Queen Victoria asking for pardon.
The executions took place on 13th of November 1849 at Horsemonger Lane Gaol. It's estimated that between thirty and fifty-thousand people attended.
'The Times' newspaper reported:
"At a quarter past eight Manning and his wife entered the (prison) chapel. The Sacrament was administered to them when the governor appeared and said that time pressed. Calcraft (the executioner) also came forward and the wretched pair were conducted to different parts of the chapel to be pinioned. The operation was performed on the male prisoner first and he submitted to it with perfect resignation. In the pinioning of Mrs. Manning a longer time was occupied. When the cords were applied to bind her arms her great natural strength forsook her for a moment, and she was nearly fainting, but a little brandy brought her round again, and she was pinioned without any resistance. She drew from her pocket a black silk handkerchief and requested that she might be blindfolded with it, a request that was acceded to. Having had a black lace veil fastened over her head, so as to completely conceal her features from the public gaze, she was conducted to the extremity of the chapel, where the fatal procession was at once formed and in a slow and solemn manner moved forwards towards the drop, the prison bell tolling."
"The procession passed along a succession of narrow passages, fenced in with ponderous gates, side rails and chevaux de frise of iron. In its course a singular coincidence happened. The Mannings walked over their own graves, as they had made their victim do over his. Mrs. Manning walked to her doom with a firm, unfaltering step. Being blindfolded she was led along by Mr. Harris, the surgeon. She wore a handsome black satin gown.""At last nine o'clock struck and shortly after the dreadful procession emerged from a small door in the inner side of a square piece of brickwork which rests on the east end of the prison roof. To reach this height a long and steep flight of stairs had to be climbed, and it only wonderful that Manning, in his weak and tottering state, was able to ascend so far. As he ascended to the steps leading to the drop his limbs tottered under him and he was scarcely able to move. When his wife approached the scaffold he turned round with his face towards the people, while Calcraft proceeded to draw over his head the white nightcap and adjust the fatal rope. The executioner then drew the nightcap over the female prisoner's head and all the necessary preparations now being completed the scaffold was cleared of all it occupants except the two wretched beings doomed to die. In an instant Calcraft withdrew the bolt, the drop fell, and the sentence of the law was fulfilled. Frederick died almost without a struggle while Maria writhed for some seconds. Their bodies were left to hang for the customary hour before they were taken down and in the evening buried in the precincts of gaol."
"Scarcely a hat or cap was raised when the drop fell and the bodies of the murderers had hardly ceased to oscillate with the momentum of their fall before the spectators were hurrying from the spot."
Charles Dickens, who was at the execution, wrote a letter to the Times expressing his revulsion:
"I was a witness of the execution at Horsemonger Lane this morning"
"I believe that the a sight so inconceivably awful as the wickedness and levity of the crowd collected at that execution this morning."
"When the two miserable creatures who attracted all this ghastly sight about them were turned quivering into the air there was no more emotion, no more pity, no more thought that two immortal souls had gone to judgement, than if the name of Christ had never been heard in this world."
One spectator at her execution remarked in a letter to the Times, "Thank God she wasn't an English woman"