<p>Significant efforts are underway to restore the ecosystem services of peatlands. In this study, map tiles (1:25,000) from the 1930s in Northern Germany were analysed to determine how the release of GHG emissions and the ecological state of peatlands have changed over the past century. In the 1930s, species-rich, moderately used grassland ecosystems were dominant. Today, species-poor stands and abandoned areas characterise peatlands, indicating a change in land use intensity and a decline in biodiversity. In bog areas, restoration measures in recent decades have resulted in positive developments. However, estimated GHG emission rates have increased considerably during this period. In the 1930s, estimated GHG emissions per ha ranged from 7.7 to 19.8 t CO₂ eq. ha⁻¹a⁻¹, whereas in recent years, they have risen to 21.6–32.2 t CO₂ eq. ha⁻¹a⁻¹. Distinct changes in land use on peatlands are required to achieve climate protection targets. Based on the results of re-surveys, strategies to reduce GHG emissions and improve botanical diversity have been recommended.</p>