Robert and Thomas Wintour the continent and again failed to elicit Spanish support, but instead met Guy Fawkes, with whom he returned to England. Robert, a devout Catholic who inherited Huddington Court near Worcester, joined the conspiracy the following year. The plot began to unravel following the delivery of an anonymous letter to William Parker, 4th Baron Monteagle, warning him to stay away from Parliament. Thomas and Catesby confronted Monteagle's brother-in-law, the recently recruited Francis Tresham, threatening to kill him, but Tresham managed to convince them of his innocence. At that stage Thomas reportedly asked Catesby to abandon the scheme, to no avail. When
Robert and Thomas Wintour negotiate an Anglo-Spanish treaty. Tassis quickly realised that any chance of a successful Catholic rebellion was unlikely, and discounted Thomas's claim that, with funding, "3,000 Catholics" would be available for the cause. After meeting with King James he wrote to Spain emphasising the need to prioritise peace with England over the freedom of her Catholics. According to contemporary accounts late in February 1604 Thomas's cousin, Robert Catesby, invited him to his house in Lambeth, but Thomas was indisposed and could not attend. Catesby sent a second letter that Thomas did respond to, and when he arrived he found his cousin