Robert and Thomas Wintour is written about the Gunpowder Plot is derived from Thomas's confession, signed on 23 November 1605; details of the so-called Spanish Treason were added three days later. One of only two confessions printed in the "King's Book" (a highly partial contemporary account of the affair), Thomas Wintour's was the only account the government had of a plotter who had been involved from the beginning; Guy Fawkes, weakened by days of torture, may have been at the heart of the group, but he was not at its first meetings. However, Antonia Fraser views the document with suspicion, not least because Thomas's
Ambrose Rookwood inciting a popular revolt to install James's daughter, Princess Elizabeth, as titular Queen. To this end he had already helped enlist nine Catholics into the conspiracy, but was running out of money and needed to recruit more men. Rookwood was a horse-breeder, and his stable of fine mounts at Coldham Hall was needed for the Midlands uprising. He had been asked to supply them with gunpowder about a year earlier, under the pretence that it was for William Stanley's regiment in Flanders—no longer an illegal operation due to the recent Treaty of London—but otherwise provided no funds for the conspiracy.