The most tragic part of the modern Romani history is the period of World War II. The 1935 Nuremberg laws about German citizenship, blood and honour and consequent Nazi decrees classified Gypsies, together with Jews and „Negroes“, as a threat to racial purity. Any marriage of “Gypsies, Negroes and their bastard offsprings” with Germans was forbidden, and any Gypsy person in such union was supposed to be sterilized. Consequently, all Gypsies were denied the Reich’s citizenship.

In 1936 the Ministry of the Interior established the Race Hygiene and Population Biology Research Centre under the leadership of Dr. Robert Ritter, a psychiatrist. Ritter worked out „a scientific theory for recognizing the presence of Gypsy blood“. His theory stated the following: „the Gypsies are characterised by hereditary asocial and criminal behaviour and these traits cannot be eliminated through any means. The only “solution” to this “problem” was Sonderbehandlung (special treatment), a euphemism for mass murder.

Accoring to the Decree on Registry of All Gypsies, Gypsy Half-Breeds and Persons Leading a Gypsy Way of Life in the Reich, all persons on this registry were supposed to undergo a race-biological examination (blood sampling, eye and hair examination, and anthropometric measurement). On the basis of this examination, they were divided into five different groups according to their levels of Gypsy and German blood.

On April 17, 1940 head of the Reich’s SS, Heinrich Himmler, ordered first transports of Gypsies into concentration camps in Poland. The Gypsies that were working in the German arms industry were forcefully sterilized.

Throughout The Third Reich, camps for beggars, undesirables and asocials were established and many Romani men were interned there. Such camps were also established in Bohemia - Léty u Písku, and in Moravia – Hodonín u Kunštátu. In 1942 they were turned into Gypsy camps, where women and children were interned as well. People from these camps were later transported to extermination camps, especially to Auschwitz. Out of the 6,500 Roma living Czech lands in 1940, less than 800 survived the war.

On December 16, 1942 Himmler issued an order – the so-called Auschwitz Decree (Auschwitz Erlass). This decree ordered deportations of all Gypsies “without consideration of blood” from the Reich and its annexed territories to Auschwitz, where a separate Gypsy part – also called the Family Section – was created for this purpose. Approximately 5,600 Roma were transported to this camp. The prisoners were labeled with black triangles (a sign for asocials) with the letter Z (from German Zigeuner, a Gypsy) on their clothes, and had identification numbers tattooed on their forearms. Roma from the Czech lands, Moravia, the Netherlands, Belgium, Northern France, Poland and the Soviet Union were transported to Auschwitz.

Dr. Joseph Mengele (also known as the “angel of death”) was appointed as the head of the camp, and he was given a free hand in conducting his “scientific research” on these people. More than 22,000 European Roma went through this camp and about 19,000 died there. On August 2, 1944, after selecting some young Roma, the remaining 2,897 prisoners from the Gypsy camp were sent to gas chambers and the section was closed down. Therefore, the 2nd of August has become The Memorial Day of the Romani Holocaust. It is estimated that more than 300,000 Roma were killed during World War II.