Using contemporary accounts of vegetation in the South Pennine landscape of northern England from the late 18th century to the present day, we describe the degradation and subsequent partial recovery of these upland mire systems in terms of their vegetation biodiversity. The historical sources highlight several species that were once common on these peatlands but which do not currently feature as positive indicator species in monitoring or restoration programmes. The use of archival sources may provide additional evidence that complements palaeoecological data when setting restoration targets. For example, the historical accounts support the palaeoecological timeline for the disappearance of Sphagnum from these landscapes. As a step toward a possible expanded set of targets for restoration works, we suggest an extended list of positive indicator species for the South Pennines which could also be applicable elsewhere in the UK. These include species such as lesser twayblade (Neottia cordata) and the club mosses (Lycopodiaceae), which were noted to be common in the 18th and 19th centuries, but which had become rare by the early 20th century. We highlight changes in land ownership and land use through the process of enclosure, as well as indirect effects from industrialisation, as the dominant interacting drivers of vegetation change.