Pax-Draconica
Pax-Draconica is a personal union of Packilvania and Drakkengard whereby the Sultan of Packilvania is also the King of Drakkengard.
Drakkengard had been ruled by Packilvania a since 1275 when the Second United Kingdom of Bakil was formed under High King Ishak I of the Zubrayn Dynasty. During the reign of the Packilvanian Communist Party, Drakkengard was reconstituted as the Drakkengard Socialist Republic, a dependent territory of the People's Republic of Packilvania in 1918. Drakkengard was granted independence from Packilvania by Sultan Amhoud I after defeating the Packilvanian Communist Party following the Second Packilvanian Civil War which ended in 1985. However, the Parliament of Drakkengard voted for Sultan Amhoud I to be the King of Drakkengard shortly afterwards.
The Parliament of Drakkengard voted that the successors of Sultan Amhoud I in terms of Packilvanian law would become the Kings (or in the unlikely event of a female returning to the throne of Packilvania, Queens) of Drakkengard. Given that the King of Drakkengard is conferred with vast powers by the Constitution of Drakkengard, Drakkengard is in reality a vassal state of Packilvania as the Sultan in his role as the Drakken King has ensured that the policies of Drakkengard align with those of Packilvania.
As a result, Pax-Draconica is more than just a personal union of two Crowns under a single person. It is also a political, economic and strategic union as citizens of Drakkengard and Packilvania can work, live and move around freely, Drakkengard's foreign relations are largely (but not entirely) aligned with Packilvanian interests and Drakkengard AND Packilvania maintain a customs union and free trade agreements.
Inasmuch as Packilvania, as the vastly more powerful nation, dictates the terms of the relationship, Drakkengard has exerted independence from Packilvania in certain areas because the Sultan delegates most of the running of Drakkengard to the Prime Minister of Drakkengard. Thus, Drakkengard maintains friendly or cordial relations with nations with whom Packilvania is otherwise outwardly hostile. Furthermore, Drakkengard controls its own finances and has its own army. Even though the Drakken Parliament is a consultative body, it exerts considerable influence over the letter of the law.
Allowing Drakkengard this relative independence is in part a strategic move on the part of the Sultan of Packilvania. It creates a buffer state between Vekaiyu and Packilvania that can mitigate direct wars between the two. It allows Packilvania to maintain indirect contacts through Drakken diplomatic efforts. Secondly, it alleviates Packilvania of the financial, political and military obligations that retaining Drakkengard as another province would entail. Nevertheless, the relationship has had challenges as the Drakken Prime Minister insisted on tariffs for goods and services produced in Drakkengard that struggled with competition from Packilvanian producers in 2008, to which the Sultan acceded. Furthermore, Drakken has a different religion (Yehudism, a branch of Paxism similar to but distinct from the Madvinism branch of Packilvania) and welcomes humans and vulpines contrary to Packilvanian perspectives and beliefs.