Population genetics investigates genetic diversity and its changes within and between populations over space and time. Genetic diversity is important for fitness, adaptive capacity, and the survival of populations and is influenced by several factors, such as mutation, selection, genetic drift and gene flow. Copper butterflies (Lycaena) are suitable for analysing structures influencing population connectivity as they potentially form more or less closed populations. However, very little is known about their genetic diversity and what influences it. Therefore, this thesis (1) provides newly developed microsatellite markers and uses genetic markers (2) to investigate genetic diversity across four different Lycaena species in the European Alps and to determine (3) which geographic and species specific factors influence population structure, (4) which large- and small-scale structures impact the population structure, (5) how natural and anthropogenic structures influence the population structure within an Alpine valley, and (6) whether and how genetic diversity changes over time. It was shown that the postglacial relict species L. helle has a relatively high genetic diversity compared to the other three species investigated. This suggests that L. helle is still able to adapt to environmental changes. Low genetic diversity was found in L. tityrus subalpinus, although high gene flow was found within one population of this species. High mountain ridges and large river valleys can act as dispersal barriers for Copper butterflies and thus have an impact on population structures. Here, dispersal ability as a species-specific factor also plays an important role, as some barriers are less likely to affect the population structure in the more mobile species L. virgaureae. Furthermore, forests, ravines and roads, but not small rivers, represent dispersal barriers for L. tityrus subalpinus within an Alpine valley. Finally, over ten years, the genetic diversity of L. hippothoe eurydame has decreased, whereas that of L. helle has remained stable. Against the backdrop of increasing global changes, it is important to understand the genomic underpinning of population structure and adaptation as well as to investigate and monitor whether populations are able to adapt to changing environmental conditions.