The distinction between ‘Lithuanians’ and ‘foreigners’ made by the law of the Grand Duchy of Lithuania with regard to eligibility for senior offices was less clear in practice. The protracted dispute, between 1591 and 1600, over the royal nomination of a ‘Pole’ as bishop of Vilna, has traditionally been presented as an expression of Lithuanian particularism after the 1569 union between Lithuania and the Kingdom of Poland. Using neglected capitular sources, this article re-examines the crucial, but underappreciated role played by the Vilna cathedral chapter in this cause célèbre. The motives for the chapter's opposition to the royal nominee cast doubt on the allegedly overwhelming importance of the defence of Lithuanian ‘sovereignty’. Instead, the case demonstrates the significance of material interests in the actions of early modern ecclesiastical corporations.