Short answers, pulled from the story.
The total number of Germans worldwide is approximately 100 million, with most living in Germany. Sizable diaspora communities exist in the United States, Brazil, Argentina, Canada, Australia, and countries of the former Soviet Union.
Deutsche derives from the Old High German term diutisc, meaning 'ethnic' or 'relating to the people.' The term was used for speakers of West Germanic languages in Central Europe from at least the 8th century onward.
The German Empire was proclaimed in 1871, after Prussia and its allies defeated the Second French Empire in the Franco-Prussian War and took Paris. The Prussian coalition also annexed the German-speaking region of Alsace-Lorraine at this time.
The Nazi movement defined Germans to include Austrians, Luxembourgers, eastern Belgians, and so-called Volksdeutsche -- ethnic Germans across Europe. The definition expressly excluded German citizens of Jewish or Roma background, and led directly to the Holocaust in which six million Jews were murdered.
Following Germany's defeat in World War II, about 12 million Germans were expelled from Central and Eastern Europe. The country was occupied and partitioned into West Germany and East Germany, which were not reunified until 1990.
Erinnerungskultur, meaning 'culture of remembrance,' refers to Germany's ongoing public commemoration of the Holocaust. It has become an integral part of modern German identity since the post-war period.