New paleoecological reconstructions are based on results of integrated investigations of a Holocene site in lower Grøndalen near Barentsburg, Spitsbergen. Fluvial, solifluctional, lacustrine, paludine (marsh environment), and marine facies give evidence of complex environmental changes. A mosaic of large grass‐moss fens and sphagnum‐hypnum palsa bogs together with dwarf shrub‐moss heaths existed during the Holocene Climatic Optimum. Solifluction processes occurred during minor cool intervals and led to the formation of lobes and fans on valley slopes. Herbaceous and hypnum‐moss swamps and moist meadows occurred during a rather warm climate in the Subboreal. There was a marked marine transgression in the early Subatlantic. Correlations were made between the main stages of environmental development in Spitsbergen, the Faroes, the Shetland Islands, eastern Greenland, and Novaya Zemlya. During the last ice age these areas supported centers of glaciation in combination with biotic refugia, where successional systems of plants were highly organized. Since late‐glacial time these systems have displayed relatively rapid dispersal to new sites as they became free of ice and water.