The census sizes of flying insect populations are rapidly declining in Europe and across the globe. This rapid decline is expected to affect the genetic diversity found in insect populations. The reliance of both crops and wild plants on pollination by flying insects places great importance on these populations and their genetic health. The four projects I present here all involve the use of genetic data from museum specimens of butterflies to track changes in genetic diversity during recent (1875-today) time. The first and current project evaluates changes in genetic diversity in two species, the apollo and clouded apollo butterfly (P. apollo and P. mnemosyne), which are both threatened with local extinction in Sweden. I am generating resequencing data from historical samples and will compare these to available sequences from contemporary butterflies. The aim of the project is to assess the remnant populations’ chances of continued survival. Two upcoming projects are aimed at understanding how changes in Sweden’s agricultural landscape in the last century have impacted several butterfly species, looking at 1) changes in genetic diversity in relation to the development of pastureland to intensive agriculture and 2) genomic signatures of adaptation to pesticide use. In these projects, I will generate and analyse resequencing data of both contemporary and historic butterfly samples. Finally, using the genetic material generated and collected during the first three projects, I will study the relation between the capacity for dispersal a butterfly species displays and the rate at which its genetic diversity has changed during both recent and evolutionary time. The overarching aim of these projects is to understand better the rates at which genetic diversity changes in wild populations of pollinators and, wherever possible, use these insights to advise pollinator conservation policy.