Although the Nazi regime never produced the "Gypsy Law" desired by Himmler, policies and decrees were passed which discriminated against the Gypsies. Gypsies were classified as "asocial" and "criminals" by the Nazi regime. From 1933 on, Gypsies were placed in concentration camps. After 1937, the Nazis started to carry out racial examinations on the Gypsies living in Germany. In 1938, Himmler issued an order regarding the 'Gypsy question' which explicitly mentioned "race" which stated that it was "advisable to deal with the Gypsy question on the basis of race." The decree made it law to register all Gypsies (including "Mischlinge" - mixed race), as well as those people who "travel around in a Gypsy fashion" over the age of six. Although the Nazis believed that the Gypsies were originally Aryan, over time they were said to have become mixed race and were classified as "non-Aryan" and of an "alien race".