Alois Derso (1888-1964) and Emery Kelen (1896-1978) were remarkable cartoonists who became internationally renowned, particularly for their depictions of efforts to build a better world following the establishment of the League of Nations, of the rise of fascism, and of the world cooperation through the United Nations that emerged in the 1940s. Their cartoons, imbued with humour, wit, gentle satire, artistry and vision, captures the Zeitgeist of an era, contribute to our understanding of these turbulent years and still resonates today. The authors analyse the extraordinary political insights revealed in them and examine all aspects of Derso and Kelen's careers and the often-overlooked role of cartoons as historical evidence. Surprisingly, no comprehensive account of their work and lives has been published until now.