In England at the end of the Middle Ages, when political unrest was mounting - leading on several occasions to the spectacular deposition of monarchs - political poetry in English, a language in full development at the time, constituted a major field of literature, taken in the broadest sense, particularly between the end of the 14th century and the 1450s. However, it takes different forms. First of all, there are long mirrors of the prince or similar (the role of history, for example, is very important), apparently centred on the theory of good government but in reality firmly rooted in their time. This is the case, for example, with the main works of two poets well known across the Channel, Thomas Hoccleve and John Lydgate, long described as propagandists in the service of the Lancastrian dynasty that came to power in 1399. But these two poets, to name but two, also composed much shorter poems, known as poems of circumstance, for a particular person or event, sometimes on commission. However, the majority of the poems of circumstance, which flourished in connection with the internal political tensions of the 15th century, were anonymous. However, like other media, they played a part in the political communication efforts of each of the parties involved in these troubles. We will present two examples that reflect the richness of these different forms of political poetry - Richard the Redeless (c. 1401) and Mum and the Sothsegger (c. 1409), written shortly after the deposition of Richard II (1399), probably by the same author. It is as much a question of revisiting the notion of 'propaganda', the use of which in the medieval period seems tricky, as it is of suggesting that the author of these works was part of a continuum of political and cultural representations, while shaping them in a dynamic rather than passive movement.