Wilhelm II, German Emperor in the context of "Ernst von Ihne"

Kaiser (/ˈkaɪzər/ KY-zər; German pronunciation: [ˈkaɪzɐ]) is the title historically used by German and Austrian emperors. In German, the title in principle applies to rulers anywhere in the world above the rank of king (König). In English, the word kaiser is mainly applied to the emperors of the unified German Empire (1871–1918) and the emperors of the Austrian Empire (1804–1918). During the First World War, anti-German sentiment was at its zenith; the term kaiser—especially as applied to Wilhelm II, German Emperor—thus gained considerable negative connotations in English-speaking countries.

Especially in Central Europe, between northern Italy and southern Poland, between western Austria and western Ukraine and in Bavaria, Emperor Franz Joseph I is still associated with Der Kaiser (the emperor) today. As a result of his long reign from 1848 to 1916 and the associated Golden Age before the First World War, this title often has still a very high historical respect in this geographical area.

The Central Powers, also known as the Central Empires, were one of the two main coalitions that fought in World War I (1914–1918). It consisted of the German Empire, Austria-Hungary, the Ottoman Empire, and the Kingdom of Bulgaria; this was also known as the Quadruple Alliance.

The Central Powers' origin was the alliance of Germany and Austria-Hungary in 1879. Despite having nominally joined the Triple Alliance before, Italy did not take part in World War I on the side of the Central Powers and later joined on the side of the Allies. The Ottoman Empire and Bulgaria did not join until after World War I had begun. The Central Powers faced, and were defeated by, the Allied Powers, which themselves had formed around the Triple Entente. They dissolved in 1918 after they lost the war.

The Pergamon Museum (German: Pergamonmuseum; pronounced [ˈpɛʁ.ɡa.mɔn.muˌzeː.ʊm] ) is a listed building on the Museum Island in the historic centre of Berlin, Germany. It was built from 1910 to 1930 by order of Emperor Wilhelm II and according to plans by Alfred Messel and Ludwig Hoffmann in Stripped Classicism style. As part of the Museum Island complex, the Pergamon Museum was added to the UNESCO World Heritage List in 1999 because of its architecture and testimony to the evolution of museums as architectural and social phenomena.

Prior to its closing in 2023, the Pergamon Museum was home to the Antikensammlung, including the famous Pergamon Altar, the Vorderasiatisches Museum and the Museum für Islamische Kunst.

The abdication of Wilhelm II as German Emperor and King of Prussia was declared unilaterally by Chancellor Max von Baden at the height of the German revolution on 9 November 1918, two days before the end of World War I. It was formally affirmed by a written statement from Wilhelm on 28 November while he was in exile in Amerongen, the Netherlands. The abdication ended the House of Hohenzollern's 300-year rule over Prussia and 500-year rule over its predecessor state, Brandenburg. With the loss of the monarchical legitimacy that was embodied by the emperor, the rulers of the Empire's 22 monarchical states also relinquished their royal titles and domains.

Wilhelm's abdication was triggered by Germany's impending defeat in World War I. In an attempt to obtain better terms from the Allies, a number of changes were made in the government and the constitution to partially democratise the Empire. The political changes were not enough to satisfy US President Woodrow Wilson, who was leading the attempt to broker an armistice. When it became clear that he wanted Wilhelm to abdicate, both the military and the government began to make various plans to save the monarchy through a regency or some other means after Wilhelm stepped down. The outbreak of the German revolution in the first days of November 1918 increased the pressure on Wilhelm to abdicate, but he continued to refuse. In order to calm the volatile situation in Berlin, Chancellor Baden, without Wilhelm's knowledge or approval, announced on 9 November that the Emperor had abdicated. Later that afternoon, Germany was proclaimed a republic, and Wilhelm went into exile in the Netherlands the next day. His official abdication came on 28 November. The 500-year-old Hohenzollern dynasty ended quietly, with almost no violence or fanfare.

When the German Empire collapsed in 1918 at the end of World War I, it was a federal union made up of three free cities and 22 kingdoms, grand duchies, duchies and principalities, with an emperor, Wilhelm II, at its head. All of the 22 ruling monarchs – including Wilhelm, who was also King of Prussia – abdicated in November 1918 during the early weeks of the German revolution of 1918–1919.

The term German Empire (Deutsches Kaiserreich) commonly refers to Germany from its foundation as a unified nation-state on 18 January 1871 until the abdication of its last Kaiser, Wilhelm II, was proclaimed on 9 November 1918. Germans, when referring to the Reich in this period under the Kaisers, 1871 to 1918, typically use the term Kaiserreich.

Captain General (Spanish: Capitán General) has been the highest rank in the Spanish Army (Ejército de Tierra) since the 18th century. A five-star rank with NATO code OF-10, it is equivalent to a field marshal of the armies of numerous countries, a general of the Army of the United States, a captain general of the Spanish Navy (Armada Española) or a Captain general of the Air Force in the Spanish Air and Space Force (Ejército del Aire y del Espacio). A Captain General's insignia consists of two command sticks under five four-pointed stars below the Royal Crown.

A personal rank of captain general was created in the Spanish Army (and Navy) as the highest rank in the hierarchy, not unlike the Marechal de France. Since King Charles IV's reign (1788–1808), the monarchs used captain general insignia when wearing uniform. Briefly abolished by the Second Spanish Republic (except one honorary promotion), it was restored during the dictatorship of Francisco Franco; Franco himself was the only holder of this rank. Since the restoration of the monarchy in 1975, the effective rank was reserved to the reigning monarch. A few posthumous honorary promotions and honorary promotions of retired officers to this rank were also made, such as José Moscardó Ituarte (1956), Agustín Muñoz Grandes (1957), Camilo Alonso Vega (1969) or Manuel Gutiérrez Mellado (1994). Some members of the Spanish Royal Family were promoted to the rank after periods of service and Queen Isabella II appointed her consort, Francis, Duke of Cádiz (1846). Two foreign monarchs, Edward VII of the United Kingdom and Wilhelm II, German Emperor, and four distinguished foreign military officers also held the honour.

The Wilhelmine period or Wilhelmian era (German: Wilhelminische Zeit, Wilhelminische Epoche) comprises the period of German history between 1888 and 1918, embracing the reign of Kaiser Wilhelm II in the German Empire from the death of Kaiser Friedrich III until the end of World War I and Wilhelm's abdication during the November Revolution.

It represented an era of creative ferment in the society, politics, culture, art, literature, and architecture of Germany. It also roughly coincided with the late Victorian and Edwardian eras in the British Empire, the Gilded Age in the United States, the Belle Époque in the Third French Republic, and the Silver Age in the Russian Empire.

Princess Irene of Greece and Denmark R.E. (Greek: Ειρήνη, romanized: Iríni; born 11 May 1942) is the youngest child and second daughter of King Paul of the Hellenes and his wife, Queen Frederica. She is the younger sister of Queen Sofía of Spain and the late King Constantine II of the Hellenes. She is also the great-granddaughter of Wilhelm II, German Emperor, who was the first grandson of Queen Victoria.