Hajdúság: a historical/ethnographic region in the central Tiszántúl (qq.v.), originally the district encompassing the six "old hajdú towns"; more broadly, from 1876 to 1950, Hajdu County with Debrecen as its center. The hajdús, originally armed "cowherds" who protected the Hungarian livestock exported on foot from marauding Turks and other armed bands, served as mercenaries during the century and a half of Ottoman occupation. István Bocskay settled the hajdús-who contracted, in perpetuity, to fight for him in times of war-on his own lands, and bestowed on them a "collective nobility", i.e., exemption from all feudal dues and services. The hajdú settlements extended in a semi-circle from southern Bihar to the mouth of the Sajó and Hernád rivers; there were also certain hajdú-type settlements in the Dunántúl and Transylvania. The hajdús' liberties, though never officially recognized, were respected in practice until they supported Francis II Rákóczi against the Habsburgs. Reduced to serfdom at the beginning of the eighteenth century, many hajdú communities continued, for generations, to petition the courts for the recognition of their old liberties. Some of the "old hajdú towns" founded by Bocskay's troops finally won back their right to self-government, and, in 1790, were recognized as the "Hajdúkerület", an autonomous administrative unit independent of the county system.