This study presents for the first time a comprehensive cross-regional analysis of community change and species loss in the managed grasslands of northern and central Germany. In the 1950/60s, relatively species-rich communities of mesophilous and moist grasslands prevailed. Total grassland area decreased by about 45 % in the past 50-60 years while the remaining grassland was largely converted into intensively managed impoverished grassland. Based on 385 relevés taken in the 1950/60s in five floodplain grassland areas that were repeated in 2008, we found that mean plot-level species richness declined by about 30 % (from 27 to 19 species) and 23 formerly characteristic species of mesophilous and moist grasslands declined significantly in their frequency. Declining species include once common taxa such as Silene flos-cuculi (Ragged robin), Cardamine pratensis (Cuckoo flower) and Anthoxanthum odoratum (Sweet vernal grass). Losses were particularly severe in insect-pollinated species; increases were observed in seven competitive nitrogen-demanding species. The regional species pool remained unchanged (299 vs. 289 taxa) but many characteristic grassland species disappeared and were replaced by generalist species that are common in other habitat types as well.