This map shows the locations where anti-Jewish riots took place during the Plague (Black Death) near 1348-1350. The map is from Encyclopaedia Judaica: Black death, vol. 4, col. 1065-1066.
Some details of the Frankfurt pogrom in 1349 are written in a historic report (german language). One of the earlier pogroms (1241) is also reported. An example of the historic information in a city in the Netherlands is found in the book "Onse Joeden" by H.D. van den Berg.