The Clerk of the Circuit Court of Cook County Archives is home to more than 500,000 naturalization petitions covering the years 1871 to 1929. More than 400,000 of these records are Declarations of Intention, 1906-1929 which were usually the first papers to be filed by those who wished to become U.S. citizens.

Because the Declaration may be the only public record of an individual immigrant, it is a significant source of documentation for genealogists and scholars.

Also, taken as a whole, the Declarations of Intention document the social changes of the immigrant experience during this era and so can be of interest to scholars and researchers from many disciplines.

This database of Declarations of Intention was created thanks to a grant from the National Historical Publications and Records Commission (NHPRC), a division of the National Archives.