This article argues that naming can reveal personal ideologies, family connections, social interactions and changes in the concerns of the inhabitants of Ireland in the sixteenth and seventeenth centuries. Ethnic and religious differences are indicated by the differing naming practices used by the Gaelic Irish, Old English and New English, Scots and Welsh inhabitants of Ireland. Much can be divined about the symbolism underlying naming practice when the names given to children are compared with those of their parents, godparents, family members and other significant individuals. The associated importance of nicknames and by-names, wordplay about names, and the circumstances under which people might change their names are also considered.