Gwinnett County was established on Dec. 15, 1818 by an act of the General Assembly. That legislation created Gwinnett, Habersham, and Hall counties from lands ceded by the Cherokee Indians on July 8, 1817 in the Treaty of the Cherokee Agency and by the Creek Indians on January 22, 1818 in the Treaty of the Creek Agency. Both treaties were necessary because the traditional boundary between the Creeks and Cherokees ran through present-day Gwinnett County. Four days after the creation of Gwinnett County, the legislature added a portion of western Jackson County.

Portions of Gwinnett County were used to create DeKalb County (1822) and Barrow County (1914). Additionally, between 1819 and 1875, portions of Gwinnett were transferred to the following counties: Hall (1819), Jackson (1819), DeKalb (1823, 1828, and 1829), Walton (1820), and Rockdale (1875).

Census

Pop. 

2000

 588,448

1990

352,910

1980

166,903

1970

72,349

1960

43,541

1950

32,320

1940

29,087

1930

 27,853

1920

30,327

1910

28,824

1900

25,585

1890

19,899

1880

19,531

1870

12,431

1860

12,940

1850

11,257

1840

10,804

1830

13,289

1820

4,589

1810

1800

1790