This study compares two seminal speeches given by Boris Johnson in the context of Brexit. The first is from 2018 during his tenure as Foreign Secretary, and the second from 2020, by which time he had become Prime Minister. The transcripts of the two complete speeches together constitute a corpus of 7,270 words. The current study applies Hunston's (2000, 2008, 2011) model of evaluation as a means of testing Johnson's attitude towards the propositions he develops through his political oratory. Using the concepts of evaluation of status and value, this model allows us to identify Johnson's degree of alignment with his representation of the world, and to perceive an ideological component in his choices here. It is hypothesized that the changes which took place in the political landscape in the time that separated the two speeches, a period of two years in which Johnson became Prime Minister and Britain left the European Union, may have had an effect on his use of evaluative language. The study reveals statistically significant findings. Johnson is found to have changed from contributing primarily world-creating propositional content in his 2018 speech to a more significant use of world-reflecting statements in his 2020 speech, and to rely in both speeches most importantly on himself as the source of information. The study also reveals a reluctance to display any hypothetical speech behaviour, and a strong preference for truth driven statements.