Most accounts of Polish history show the two centuries after the end of the Jagiellon Dynasty as a time of decline leading to foreign domination, but Poland-Lithuania remains an influential player in European politics and a vital cultural entity through most of the period.

The death of Sigismund II Augustus in 1572 is followed by a three-year interregnum during which adjustments are made in the constitutional system.

The lower nobility is now included in the selection process, and the power of the monarch is further circumscribed in favor of the expanded noble class.

From this point, the king is effectively a partner with the noble class and constantly supervises by a group of senators.

Once the Jagiellons pass from the scene, the fragile equilibrium of the commonwealth government begins to go awry.

The constitutional reforms make the monarchy electoral in fact as well as name.

As more and more power goes to the noble electors, it also erodes from the government's center.