Kęstutis ruled as Duke of Trakai under an unusual co-governance arrangement with his brother Algirdas, dividing the Grand Duchy along functional lines — Algirdas managing eastern expansion while Kęstutis held the western frontier against the Teutonic Knights. That frontier pressure almost certainly shaped the practical need for small silver currency capable of paying troops and suppliers in a region under near-constant military stress. Kęstutis was eventually strangled on orders of his nephew Jogaila in 1382, ending one of the more capable military careers in medieval Baltic history.
Kęstutis ruled as Duke of Trakai under an unusual co-governance arrangement with his brother Algirdas, dividing the Grand Duchy along functional lines — Algirdas managing eastern expansion while Kęstutis held the western frontier against the Teutonic Knights. That frontier pressure almost certainly shaped the practical need for small silver currency capable of paying troops and suppliers in a region under near-constant military stress. Kęstutis was eventually strangled on orders of his nephew Jogaila in 1382, ending one of the more capable military careers in medieval Baltic history.