During the 7th century CE, many predominantly Christian regions fell under Islamic political control, including Spain, Egypt, Palestine, Syria, and the Caucasus. This began a long, complex process whereby these ancient Christian societies become medieval Islamic societies. Although forced conversion was relatively uncommon, tensions sometimes spilled over into violence and Christians commemorated the victims as saints. This talk will introduce these Christian martyrs against the backdrop of early relations between Muslims and Christians, ancient ideas of martyrdom, and the formation of what is often called ‘Islamic civilization.’