OK, I'm game:
1700s: Felipe V of Spain spins off South America to one of his sons or ome other relative who proceeds to allow it to decentralize into quarelling entities nominally subject to him. What could we call such an entity?
1700s: After their loss of Hungary in 1699 the Ottoman leadership loses clout and grants hereditary rights of autonomy to princes and viziers in various parts of the empire such as Serbia, Arabia and Egypt. Though nominally subjects of the Sultan they become more and more independent to the point of pursuing their own foreign policies.
1600s: Sweden detaches Brandenburg, Mecklenburg, Holstein, Pomerania from the HRE and forms its own Protestant Confederation only to have the member states constantly scheming against whatever central authority Stockholm tries to assert. Whether this would last until 1800 is doubtful. Sweden would have to beat Russia in the Northern War.
1600s-1800: Didn't this kind of exist under the Manchu in China? Didnt they consider Tibet, Mongolia, Vietnam and Thailand as part of their empire even though those areas had other ideas?
1600s: The Romanovs are not so successful in centralizing their authority and the areas around Muscovy are able to retain a good deal of autonomy even though they are nominally part of the empire.
Late 1688: No Glorious Revolution in England. The England of James II remains divided and at cross-purposes with itself allowing for a rambunctious Ireland and Scotland.
Whaddya Think?