Petitioning Osiris re-edits, re-analyses, and re-contextualises the "Old Coptic Schmidt Papyrus" and "Curse of Artemisia" - written petitions to different manifestations of Osiris - among the Letters to Gods in Demotic, Greek, and Old Coptic from Egypt. The textual traditions of the Letters to Gods, to the Dead, and Oracle Questions which evidence that ritual tradition of petitioning deities are contextualised among contemporary textual traditions, such as Letters and Petitions to Human Recipients, and Documents of Self-Dedication, and compared to later ritual traditions such as proactive and reactive curses without and with judicial features (so-called Prayers for Justice) in Greek and Coptic from Egypt and the Eastern Mediterranean. As with all other Letters to Gods, the Old Coptic Schmidt Papyrus and Curse of Artemisia evidence not only the struggles and aspirations of their petitioners, but also the way in which they conceptualised that they could bring about desired outcomes in their lived experience by engaging divine agency through a reciprocal relationship of human-divine interaction. Petitioning Osiris therefore provides a starting point and springboard for readers interested in these, or comparable, textual and ritual traditions from the Ancient World.