In 1809 Portland, whose health was failing, resigned. The new Tory Prime Minister was Spencer Perceval. In April 1812 he brought Sidmouth into the cabinet. A month later, on 11 May 1812, Perceval was assassinated. The premiership passed to the Earl of Liverpool, who failed to attract Grenville. This was a further stage in the development of a two-party system—just about all Tories supported the government and all Whigs opposed it.