The so-called "Rhineland Bastards" (it is a pretty insulting name seeing as to how bastard is a slur for extramarital children) were the children of African and African-American Entente soldiers, who had been part of the Entente occupation of Rhineland after WWI and German women.

After WWI, France as a precaution from renewed German attacks insisted on occupying the territories left of the Rhine as well as establishing military bridgeheads on the right side of the Rhine. These were Germany's most heavily industrialized territories, where both its heavy industry and coal mining were located. This was seen as both a way to prevent another German attack from these territories as well as a means to force Germany to pay its reparations. Despite this provision being part of the Versailles Peace Treaty, there is a whole history of Germany trying to resist this occupation, which in turn caused a massive inflation within Germany in the beginning of the 1920s as well as other consequences but that is tangential to this history.

Anyways, from January 1919 forward French, Belgian, British, and initially American troops occupied the Rhineland (and in 1923 also the Ruhrterritories). Among these troops was a sizeable portion of colonial troops, including soldiers from North and Subsaharan Africa, especially as part of the French occupation contingent. A relatively high number of German women married soldiers from the occupying forces, while many others had children by them out of wedlock. The total number of children resulting from the occupation (including those of white occupation soldiers) is estimated at 160,000 to 180,000. The number of children with an African father is hard to know since German authorities back in those days (and still not today with the exception of the twelve years of Nazi rule) did not register someone's "race" upon birth. Some, like Richard Evans, estimate the number of so-called "Rhineland Bastards" (not all of whom were bastards, meaning not all were born out of wedlock) with no more than five or six thousand but other estimates go as high as 17000 black children.

Even the Nazis were unable to conclusively count them. While the so-called "Rhineland Bastards" were probably the group the German racial discourse concerning Black Germans revolved around. Seen as a product of a loathed occupation and additionally as an example of the "pollution" of the German "race", these individuals were probably the most discriminated against of all the Black people living in Germany.

Hitler wrote about them in Mein Kampf: “Jews were responsible for bringing Negroes into the Rhineland, with the ultimate idea of bastardizing the white race which they hate and thus lowering its cultural and political level so that the Jew might dominate.” Together with all other Black people, the "Rhineland Bastards" were deemed non-Aryan under the Nuremberg laws and therefore forbidden from marrying "Aryans".

Additionally, they were forced to undergo sterilization from 1937 on. Organized by the two most prominent German eugenicists, Eugen Fischer and Fritz Lenz, about 400 children deemed as "Rhineland Bastards" were forcibly sterilized from 1937 on.

It bears mentioning however that these 400 were far from all Black people in Germany and that beyond this heinous attack on part of the group of Germans who were children of the occupation soldiers, there was no coherent policy of Nazi Germany towards Black people except a campaign for social isolation, which given the racially charged climate of the time and the use of Black people (espeically in the context of Jazz) as a signifier for the degeneracy of the USA, hardly needed help. Black people were forbidden from entering University, lost their jobs and were ostracized. Beyond that no coherent policy was ever formed. Robert Kestings describes a case in which a local labor agency petitioned the Reich Security Main Office on how to deal with an Afro-German who was unable to find employment due to his criminal record and got the response that the population was too small to warrant the formulation of an overarching policy and therefore they could deal with it as they saw fit.

Beyond that, experiences differed to some extent, especially in the context of the war. There was a small number of Black soldiers serving in the Wehrmacht through recruitment during the African campaigns but as a general rule, Black POWs of various Allied Armies were treated worse than their non-Black counterparts. Black POWs were often transferred to Concentration Camps and various survivors report that they were subjected to cruel medical experiments because they were Black.

The children of occupational soldiers from the Rhineland as well as a number of black Germans who had lived in Germany dating back to its colonial ventures in Africa made up about 25-30.000 people during the 1920s and they respectively their children and grandchildren still live in Germany where they comprise a portion of this country's Afro-Germany community. It is estimated that today 500.000-800.000 Afro-Germans live in Germany (many of them descendants of black emigrants in Eastern Germany too), meaning that almost 1% of the total German population is black.

Sources:

• Campt, Tina. Other Germans: Black Germans and the Politics of Race, Gender, and Memory in the Third Reich. Ann Arbor: University of Michigan, 2004.

• Friedman, Ina R. “No Blacks Allowed.” In The Other Victims: First-Person Stories of Non-Jews Persecuted by the Nazis, 91-93. Boston: Houghton Mifflin, 1990.

• Kesting, Robert (2002). "The Black Experience During the Holocaust". In Peck, Abraham J.; Berenbaum, Michael. The Holocaust and History: the Known, the Unknown, the Disputed, and the Reexamined. Indiana University Press.

• Robert W. Kestling: Blacks Under the Swastika: A Research Note , The Journal of Negro History, Vol. 83, No. 1 (Winter, 1998), pp. 84-99

• Lusane, Clarence. Hitler’s Black Victims: The Historical Experiences of Afro-Germans, European Blacks, Africans, and African Americans in the Nazi Era. New York: Routledge, 2002.