They'll fit in well, as Argentina is also one of the most racist countries on earth.
By mid 1700s 50% of the population of Argentina was black, this decreased to around 1/3 at the beginning of the 1800s. However, by late 19th early 20th century the Black population had decreased significantly to around 2%.
Thousands of black men were recruited into the military during the wars of independence and the Paraguayan War (1864–1870), serving on the front lines. Blacks were more likely to be sent to the front line as a result, Black soldiers experienced high mortality rate.
Many died because of mistreatment and racist policies, others perished because of disease, as Blacks were treated as 2nd class citizens. The indigenous Indian population suffered just as bad.
Today, Argentina's white population sits at around 90%. Making it the most "white country" in the Americas. White Ashkenazi Jews will fit in perfect with such a racist society.
