This monograph examines the mosaic floors of the Early Christian basilicas of Kos island brought to light by the Italian Archaeological School of Athens during the military occupation. The documentation consisted of mostly unpublished archive material - watercolours, blueprints, photographs of the mosaics taken at the time of the findings. Work on the synthesis of the mosaics' different aspects was completed to better define the aspects of the Late Antiquity Koan decorative repertoire and its ties with the production of Imperial times; to understand the artisans working methodology and to distinguish the workshops; to find areas of diffusion of the decorative repertoire.