Climate change enhances the incidence of extreme weather events and plant range shifts to higher altitudes and latitudes. Extreme weather and range-shifting plant species may have direct effects on soils and the community composition of soil biota that can remain as legacies affecting plant-soil interactions in subsequent growing seasons. However, little is known about soil legacy effects induced by multiple factors of climate change on above-belowground interactions in plant communities invaded by range expanders. In a seven-years outdoor mesocosm experiment, soil inocula were introduced from south-eastern and north-western Europe. I show that these soil legacies were altered differently by both range-expanding plants and extreme drought and their interactions, and that these legacy effects altered leaf chemistry and aboveground insects. The legacy effects lasted for minimally one year. I conclude that that soil can contain ‘memories’ of complex climate change events as changes in soil community composition affecting plant aboveground interactions.