During the tenth century AD, Harald Bluetooth ruled Denmark from the royal seat at Jelling. The two extant Jelling mounds are traditionally associated with Harald's parents, Gorm and Thyra, about whom we know little. Unusually, the name Thyra appears on both Jelling runestones and on several others from the region. If all refer to the same person, she would be commemorated on more runestones than anyone else in Viking-Age Denmark. The authors use 3D-scanning to study rune carving techniques, combined with analyses of orthography and language, concluding that the Jelling 2 and Læborg stones are linked by the hand of the carver Ravnunge-Tue. The results suggest Thyra played a pivotal role in the emergence of the Danish state.