The Eikon Basilike (Royal Portrait) contains accounts of various events and hardships encountered by Charles I in the years preceding his defeat and was probably, at least in part, written by the king himself. The book was first published ten days after the monarch’s execution in 1649 and quickly became one of the biggest-sellng books of the seventeenth century. Four lengths of blue silk ribbon are attached to the binding and an inscription inside the book describes these as having formed Charles I’s garter ribbon, seen in the portrait nearby. Recent radiocarbon dating indicates that the ribbon is likely to date from between 1631 and 1670.