The present article explores how women of power engaged in diplomatic efforts via forms of epistolary privacy by analysing private letters between Elizabeth I and Anna of Saxony in the late 1570s and early 1580s. Through a close examination of how their exchanges moved from very public matters to more personal requests, the authors show how early modern notions of privacy offered strategic communication prompts that could be used effectively by women in political negotiations. The intersection between these zones of privacy with the very public matters being addressed in Elizabeth’s and Anna’s epistolary exchange makes explicit how noble women could develop their own private politics, becoming active agents of diplomacy even in periods of extreme religious and political turmoil through personal connections within female noble circles.