The dataset contains results from three early Paleozoic geological units: the approximately 500 Ma Santa Angélica and Venda Nova plutons of the Araçuaí orogen, Brazil; the approximately 470 Ma Younger Gabbros of Aberdeenshire, Scotland; and the approximately 430 Ma Silurian volcanic succession of the East Mendips Inlier, southern Britain. The deposited files include specimen- and site-level paleointensity results, paleomagnetic directional data, rock-magnetic measurements, methodological and selection-criteria information, and the processed data used to construct the long-term virtual dipole moment and geomagnetic polarity-reversal-frequency synthesis. Upload-ready files for analysis using Paleomagnetism.org and Paleointensity.org are also included, together with file-level metadata. These data provide new estimates of geomagnetic field strength from approximately 500-430 Ma and help fill a major gap in the Phanerozoic paleointensity record. They were used to investigate the relationship between long-term geomagnetic dipole moment and polarity reversal frequency. The data relate to three study areas: the Santa Araçuaí and Venda Nova plutons in the Araçuaí orogen, EspÃrito Santo, southeastern Brazil; the Younger Gabbros of Aberdeenshire, northeast Scotland; and the Early Wenlock volcanic succession of the East Mendips Inlier at Stokes Quarry, Somerset, southern Britain. Data support the paper "Geomagnetic dipole moment and polarity reversal frequency covary on a ~200-million-year timescale". The paper identifies the three datasets and their respective ages and locations, and states that the deposit contains upload-ready analytical files, metadata and the data used to construct the long-term synthesis."