ENThe levée‑en‑masse of the nobility of the Duchy of Samogitia and the formation of the confederation of the Lithuanian army in 1696 were an element of the civil war that lasted in the Grand Duchy of Lithuania in the years 1696–1700. They were a form of action by the leading families of Lithuanian magnates and smaller nobles against the growing dominance of the Sapieha family. Both of these events were closely followed by Johann Reyer, a Brandenburg envoy who was in Ducal Prussia, on the border with Lithuania. His detailed reports for the Elector of Brandenburg, Frederick III, and the correspondence with agents in Lithuania attached to them, show a picture of a poorly prepared anti‑ Sapieha enterprise by the opposition, which was carried out even worse, and which ended in its capitulation just a month after the first calls for action. Keywords: history of the Grand Duchy of Lithuania, civil war in Lithuania in the 17th century, confederations of the Lithuanian army, levées‑en‑masse of the Lithuanian nobility.