organized 8/7/1852 After the Treaty of Guadalupe Hidalgo of 1848 the area became part of San Patricio County. In the same year the region was further subdivided and became part of Cameron County. Hidalgo County was formed 1/24/1852 and named for Miguel Hidalgo y Costilla, who gave the "cry for Mexican independence" from Spanish rule. In 1852 La Habitación was renamed Edinburgh and made county seat. Because of their sense of neglect by state and federal governments, residents adopted the name "Republic of Hidalgo."