Chatham joined with Pitt and Shelburne to oppose the Fox–North coalition of 1783 but generally kept a low profile during these years. Pitt became prime minister in December 1783. Chatham supported his brother in the Lords but did not take office. In February 1784 on the way back from an event in the City of London, the brothers were attacked by a mob likely organised by supporters of their rival Charles James Fox. In the subsequent 1784 general election Pitt won a decisive victory, securing his government's future. Due to his wife's severe illness, Chatham did not consider himself able to join his brother's government for the next few years, despite rumours linking him to various posts.