The aim of this chapter is the exploration of the ways in which the noble citizens of Poland-Lithuania responded to questions arising in 1572 after the death of King Sigismund Augustus by establishing the so-called “free election”, a unique mode of electing the monarch that distinguished the Polish-Lithuanian Commonwealth from the rest of early modern Europe. From 1573 to 1764 all Polish monarchs were elected in accordance with the rules of the electio viritim, while the quasi-constitution of the republic became the Henrician Articles formulated in 1573. A useful political tool during the early elections turned out to be a reference to “Jagiellonian blood”, an indication of continued noble attachment to dynastic continuity even within an electoral framework. Nevertheless, this early procedure, based on a commitment to republican ideals, ensured unprecedented levels of civic political engagement. Due to a complex web of internal and external socio-political developments of the eighteenth century, this highly participatory model later gave way to a re-establishment of hereditary monarchy, accomplished in the Constitution of 3 May 1791. This development, paradoxical yet in tune with Enlightenment ideas shaping the European political sphere, was accompanied by a secularisation of notions of legitimacy and power, a transformation that reflected the wider ideological changes in the Polish-Lithuanian Commonwealth and its political nation.