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The Hercynian mountain ranges were islands of mountain glaciation and alpine tundra in a Central European ice‐free corridor during the Late Pleistocene. Today they are notable areas of glacial landforms, alpine‐forest free areas, peatlands and woodlands. However, our knowledge of the Lateglacial and early Holocene environmental changes in this region is limited. We present a new multi‐proxy reconstruction of a mid‐altitude environment in the Bohemian Forest spanning this period. A core (5.2 m length) in the Černé Lake cirque (1028 m a.s.l.) was subjected to lithological, geochemical, pollen and macrofossil analysis supplemented by two optically stimulated luminescence (OSL) and 10 AMS radiocarbon dates. We determined the impact of regional and supraregional climate changes on the environment. The two most significant changes in sedimentation during the Lateglacial (17.6 and 15.8–15.5 cal. ka BP) were synchronous with regional glacial chronostratigraphy. Unlike Central European mountain ranges, in the Bohemian Forest the Younger Dryas was not coincident with glacier re‐advance, but was a dry, cold episode with low lake levels, which prevailed until the early Preboreal. Plant macrofossils indicate local establishment of Betula nana and Betula pendula/pubescens at 15.4–13.4 cal. ka BP. Comparison with Holocene records from Central Europe shows a similar immigration history of vegetation at mid and higher altitudes. The tree line exceeded an altitude of ~1000 m a.s.l. around 10.5 cal. ka BP and coincided with rapid geochemical changes in the sediment. The 8.2 ka BP event did not have any response in the sedimentary record, but corresponded to stabilization of the Picea abies population and expansion of Fagus. Fagus colonized the Bohemian Forest earlier than other Hercynian mid‐mountains, but never predominated in the composition of the forest at higher elevations. Abies alba was the last tree species that immigrated to the study area.

The invasion history of archaeophytes (i.e. alien taxa that were introduced into Europe prior to AD 1500), their effect on past vegetation and their present status based on their residence time were studied. The residence times of archaeophytes range from 7500 to 500 years. It is likely that species with other functional traits came at different times. We summarized assemblages of macroremains obtained from the Archaeobotanical Database of the Czech Republic. The data based on 202 archaeological sites cover the period from the Neolithic to the Early Middle Ages. We found 123 alien species and 94 synanthropic species native in the Czech Republic. Three waves of immigration of increasing magnitude were distinguished: (i) the Neolithic, (ii) the Bronze Age, and (iii) the Early Middle Ages. The first phase of synanthropic plant immigration was characterized by the prevalence of native and alien generalist species, which are still very abundant, sharing both ruderal and segetal habitats. Specialist weeds of cereal fields occurred only since the Eneolithic. In the ruderal flora, the successive development started from a stage dominated by species associated with disturbance of less fertile soils and species that need nutrient-rich soils prevailed later. The composition of the oldest grassland flora corresponded with that of short lawns at disturbed and/or trampled sites, whereas a sudden increase in meadow species occurred in the Late Bronze Age. Since the Middle Ages, pastural species, avoided by grazing animals, indicate the intense use of pastures and their expansion into wet conditions. The species that arrived early in this era, i.e. in the Neolithic, are currently more successful than the later arrivals. Such a trend cannot be explained by the length of time they have had to naturalize and spread because all archaeophytes have been here long enough, whether they arrived early or late, to be

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