In january 1910, a major flood occurred involving all the rivers of the Rhine Graben (France, Germany, Switzerland), but with huge differencies in the spatial results : damages were much more higher on the left side of the Rhine (Alsace), because of the delay in rivers corrections, generating different vulnerabilities. This example shows the necessity of the contextualization of historic floods in time and space. Because the informations concerning floods are linked with sources and the sources are linked with damages. Flood chronology appears much more as a chronology of the vulnerability to flood and of the landuse changes. This paper based on a flood chronology from 1800 to 2015 extracted from the TRANSRISK database (1480-2015), propose to analyse temporal and spatial variations of flood intensity, in relation with landuse changes and vulnerability evolution, using a geohistorical, transnational and comparing approach. At the end, we will also study the consequences of flood evolution on risk culture, and how to rebuild and share it.