The arrival of Dieter Wislizeny and Alois Brunner marked the final steps of the Operation Rosenberg, so named after Alfred Rosenberg, a Nazi theorist and head of the foreign-affairs department. Rosenberg considered Thessaloniki an important Jewish center, a city characterized by the cosmopolitanism and economic power of its Jewish people. The operation was characterized by the looting of properties, cultural centercenters and synagogues, the shutting down of the stores, newspapers and various institutions, the requisition of houses and Jewish hospital which were used by the Nazi army. The final act of the operation dictated the registration of the population, the order to wear the yellow star, not to ride on the tramway, not to use the telephone, not to walk in the streets at night, and finally the creation of two ghettos, into which the Jews were obliged to move.