Eastern Cistern B on the Ad-Deir Plateau is unusual in its breadth and variety of ceramic vessels represented by thousands of sherds. These sherds raised significant questions about the purpose and use of the vessels that they originally came from. This thesis argues that the ceramic vessels that were deposited in Eastern Cistern B represent the deposited remains of an ancient Nabataean ritual feast. Furthermore, this thesis also helps to answer the questions surrounding what the ceramic containers once held and their relationship to that ritual meal. This thesis identified residues absorbed within the ceramic fragments through the use of a gas chromatographer-mass spectrometer analysis. The data demonstrated that the vessels once contained remains of medicinal plants, such as crocus, oleander, and others as well as post deposition contaminants throughout the majority of the samples. Those contaminations and other limitations mentioned in this thesis may provide a basis for future investigations for absorbed residue analysis in Petra, Jordan. In turn, the relationship between the medicinal plants and the feast at Eastern Cistern B suggests that a healing ritual possibly accompanied a meal suggesting archaeologists begin examining this and other associated events that accompanied ritual feasts in and among the Nabataeans and in the ancient Near East more broadly.