The Province of Posen (German: Provinz Posen, Polish: Prowincja Poznańska) was a province of Prussia from 1848–1918 and as such part of the German Empire from 1871 to 1918. The area was about 29,000 km².

The territory of later province, roughly corresponding to the region of Greater Poland, had become Prussian in 1772 (Netze District) and 1793 (South Prussia) during the partitions of Poland. After Prussia's defeat in the Napoleonic Wars, the territory was attached to the Duchy of Warsaw in 1807 during the Treaty of Tilsit. In 1815 during the Congress of Vienna, Prussia gained the western third of the Warsaw duchy, which was about half of former South Prussia. Prussia then administered this province as the semi-autonomous Grand Duchy of Posen, which lost most of its exceptional status in 1830. While the local Posen (Poznań) Parliament voted 26 to 17 votes against joining German Confederation, on 3 April 1848 the Frankfurt Parliament ignored the vote, forcing status change to a normal Prussian province and its integration in the German Confederation.

Wernher Magnus Maximilian, Freiherrvon Braun (March 23, 1912 – June 16, 1977) was a German-born rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and, subsequently, the United States.

In his 20s and early 30s, von Braun was the central figure in Germany's rocket development program, responsible for the design and realization of the V-2 combat rocket during World War II. After the war, he and some of his rocket team were taken to the United States as part of the then-secret Operation Paperclip. Von Braun worked on the United States Army intermediate range ballistic missile (IRBM) program before his group was assimilated by NASA, under which he served as director of the newly formed Marshall Space Flight Center and as the chief architect of the Saturn V launch vehicle, the superbooster that propelled the Apollo spacecraft to the Moon. According to one NASA source, he is "without doubt, the greatest rocket scientist in history". His crowning achievement was to lead the development of the Saturn V booster rocket that helped land the first men on the Moon in July 1969. In 1975 he received the National Medal of Science.

Heinrich Luitpold Himmler (pronounced [ˈhaɪnʁɪç ˈluˑɪtˌpɔlt ˈhɪmlɐ] ( listen) 7 October 1900 – 23 May 1945) was Reichsführer of the Schutzstaffel (SS), a military commander, and a leading member of the Nazi Party (NSDAP). As Chief of the German Police and the Minister of the Interior from 1943, Himmler oversaw all internal and external police and security forces, including the Gestapo (Secret State Police). Serving as Reichsführer and later as Commander of the Replacement (Home) Army and General Plenipotentiary for the entire Reich's administration (Generalbevollmächtigter für die Verwaltung), Himmler was one of the most powerful men in Nazi Germany and one of the persons most directly responsible for the Holocaust.

As overseer of the concentration camps, extermination camps, and Einsatzgruppen (literally: task forces, often used as death squads operating to the rear of frontline troops to murder Jews, communists and 'untermensch' in occupied territories), Himmler coordinated the killing of some six million Jews, between 200,000 and 500,000 Roma, many prisoners of war, and possibly another three to four million Poles, as well as other groups whom the Nazis deemed unworthy to live, including people with physical and mental disabilities, Jehovah's Witnesses, members of the Confessing Church, and homosexuals. Shortly before the end of the war, he offered to surrender both Germany and himself to the Western Allies if he were spared prosecution. After being arrested by British forces on 22 May 1945, he committed suicide the following day before he could be questioned.