5 surviving letters between Pope Gregory the Great and Theudelinda, spanning 591-603 AD.
Gregory, servant of the servants of God, to our daughter in Christ, the most excellent Queen Theudelinda.
Gregory, servant of God, to our most excellent daughter Theudelinda.
Theudelinda, queen, to the most blessed and holy Gregory, bishop of Rome.
Gregory to our most excellent daughter Theudelinda.