Question: Whose defeat ended the anti-Polish campaign that began with the idea to unify all the German and possibly also Germanic-speaking peoples in a single nation-state known as "Großdeutschland".?
Context: Hegemonic stability theory (HST) is a theory of international relations, rooted in research from the fields of political science, economics, and history.  HST indicates that the international system is more likely to remain stable when a single nation-state is the dominant world power, or hegemon.  Thus, the fall of an existing hegemon or the state of no hegemon diminishes the stability of the international system.  When a hegemon exercises leadership, either through diplomacy, coercion, or persuasion, it is actually deploying its "preponderance of power."  This is called hegemony, which refers to a state's ability to "single-handedly dominate the rules and arrangements ...[of] international political and economic relations."  HST can help analyze the rise of great powers to the role of world leader or hegemon, which have been ongoing since the 15th century.  Also, it can be used to understand and to calculate the future of international politics through the discussion of the symbiotic relation between the declining hegemon and its rising successor. The First Melillan campaign, also called the Melilla War or the Margallo War (after Juan García y Margallo, the Spanish governor of Melilla whose defeat and death infuriated the Spanish public) in Spain, was a conflict between Spain and 39 of the Rif tribes of northern Morocco, and later the Sultan of Morocco, that began in October 1893, was openly declared November 9, 1893, and was resolved by the Treaty of Fez in 1894. The Tai () ethnicity refers collectively to the ethnic groups of southern China and Southeast Asia, stretching from Hainan to eastern India and from southern Sichuan to Laos, Thailand, and parts of Vietnam, which speak languages in the Tai-Kadai language family, and share similar traditions and festivals, such as Songkran.  Despite never having a unified nation-state of their own, the peoples also have historically shared a vague idea of a "Siam" nation, corrupted to Shan or Assam in some places, and most self-identify as "Tai" . Stateira II (Greek: Στάτειρα ; died 323 BC), possibly also known as Barsine, was the daughter of Stateira I and Darius III of Persia.  After her father's defeat at the Battle of Issus, Stateira and her sisters became captives of Alexander of Macedon.  They were treated well, and she became Alexander's second wife at the Susa weddings in 324 BC.  At the same ceremony Alexander also married her cousin, Parysatis, daughter of Darius' predecessor.  After Alexander's death in 323 BC, Stateira was killed by Roxana, his first wife. Pan-Germanism or Pan-Germanicism (German: "Pangermanismus" or "Alldeutsche Bewegung" ; see also Pan-Germanicism) is a pan-nationalist political idea.  Pan-Germanists originally sought to unify all the German and possibly also Germanic-speaking peoples in a single nation-state known as "Großdeutschland". The Expulsion of Poles by Germany was a prolonged anti-Polish campaign of ethnic cleansing by violent and terror-inspiring means lasting nearly half a century.  It began with the concept of Pan-Germanism developed in the early 19th century and culminated in the racial policy of Nazi Germany that asserted the superiority of the Aryan race.  The removal of Poles by Germany stemmed from historic ideas of expansionist nationalism.  It was implemented at different levels and different stages by successive German governments.  It ended with the defeat of Nazi Germany in 1945. German Eastern Marches Society (German: "Deutscher Ostmarkenverein" , also known in German as "Verein zur Förderung des Deutschtums in den Ostmarken ") was a German radical, extremely nationalist xenophobic organization founded in 1894.  Mainly among Poles, it was sometimes known acronymically as "Hakata" or "H-K-T" after its founders von Hansemann, Kennemann and von Tiedemann.  Its main aims were the promotion of Germanization of Poles living in Prussia and destruction of Polish national identity in German eastern provinces.  Contrary to many similar nationalist organizations created in that period, the Ostmarkenverein had relatively close ties with the government and local administration, which made it largely successful, even though it opposed both the policy of seeking some "modo vivendi" with the Poles pursued by Chancellor Theobald von Bethmann Hollweg and Leo von Caprivi's policies of relaxation of anti-Polish measures.  While of limited significance and often overrated, the organization formed a notable part of German anti-democratic pluralist part of the political landscape of the Wilhelmine era. Tanausu (also Tanausú and Atanausu) (died 1493) was the Guanche ruler of Aceró, on the island of La Palma (known to the original population as Benahoare), whose defeat by the Castilians marked the final conquest of that island.  The island of Tenerife, conquered in 1495, was the last of the Canary Islands to fall under European control.  His name has been translated as "The obstinate" or "He who has kidneys." The Siege of Berat in Albania by the forces of the Angevin Kingdom of Sicily against the Byzantine garrison of the city took place in 1280–1281.  Berat was a strategically important fortress, whose possession would allow the Angevins access to the heartlands of the Byzantine Empire.  A Byzantine relief force arrived in spring 1281, and managed to ambush and capture the Angevin commander, Hugo de Sully.  Thereupon, the Angevin army panicked and fled, suffering heavy losses in killed and wounded as it was attacked by the Byzantines.  This defeat ended the threat of a land invasion of the Byzantine Empire, and along with the Sicilian Vespers marked the end of the Western threat to reconquer Byzantium. The Master of the Gamblers (known in Italian as Maestro dei Giocatori) ("fl" 1620 – 1640) is the notname given to a painter active in Rome and possibly also in Naples in the second and third decade of the 17th century, whose subject matter and style rank him among the Caravaggisti (followers of Michelangelo Merisi da Caravaggio).  The artist depicted genre subjects and still life elements in his works in a stark naturalist manner.  The identity and nationality of the artist are not known.  Art historians have yet to arrive at a unanimous view on the nationality, work location and the oeuvre of the artist.  He may have been Italian, but a northern European background has also been proposed.
Answer: Nazi Germany