Illinois's at-large congressional district

From statehood to 1833, Illinois had only one congressional district, and therefore it was at-large.

Representative	Party	Years	Cong ress	Electoral history
John McLean	Democratic-Republican	December 3, 1818 – March 3, 1819	15th	Elected in 1818. Lost re-election.
Daniel P. Cook	Democratic-Republican[lower-alpha 1]	March 4, 1819 – March 3, 1825	16th 17th 18th 19th	Elected August 2, 1819. Re-elected August 7, 1820. Re-elected August 5, 1822. Re-elected August 2, 1824. Lost re-election.
	Anti-Jacksonian	March 4, 1825 – March 3, 1827
Joseph Duncan	Jacksonian	March 4, 1827 – March 3, 1833	20th 21st 22nd	Elected August 7, 1826. Re-elected August 4, 1828. Re-elected August 1, 1831. Moved to 3rd district.
District inactive March 3, 1833

From 1863 to 1873 there was one at-large seat in addition to the districted seats.

Representative	Party	Years	Cong ress	Electoral history
James C. Allen	Democratic	March 4, 1863 – March 3, 1865	38th	Elected in 1862. Lost re-election.
Samuel W. Moulton	Republican	March 4, 1865 – March 3, 1867	39th	Elected in 1864. Retired.
John A. Logan	Republican	March 4, 1867 – March 3, 1871	40th 41st	Elected in 1866. Re-elected in 1868. Re-elected in 1870, but resigned to become U.S. Senator.
Vacant		March 4, 1871 – November 7, 1871	42nd
John L. Beveridge	Republican	November 7, 1871 – January 4, 1873		Elected to finish Logan's term. Resigned to become Lieutenant Governor.
Vacant		January 4, 1873 – March 3, 1873

From 1893 to 1895, there were two at-large seats in addition to the districted seats.

Years	Cong ress		Seat A				Seat B
			Representative	Party	Electoral history		Representative	Party	Electoral history
March 4, 1893 – January 12, 1895	53rd		John C. Black	Democratic	Elected in 1892. Resigned to become U.S. Attorney.		Andrew J. Hunter	Democratic	Elected in 1892. Lost re-election in the 19th district.
January 12, 1895 – March 3, 1895			Vacant

Two at-large seats were re-established March 4, 1913. From that date to January 3, 1943, there were two at-large seats, which was reduced to one seat from 1943 to 1949. Representation by districts also continued during this period. The at-large seat was abolished effective January 3, 1949.

Years	Cong ress		Seat A				Seat B
			Representative	Party	Electoral history		Representative	Party	Electoral history
March 4, 1913 – March 3, 1915	63rd		Lawrence B. Stringer	Democratic	Elected in 1912. Retired.		William E. Williams	Democratic	Elected in 1912. Re-elected in 1914. Lost re-election.
March 4, 1915 – March 3, 1917	64th		Burnett M. Chiperfield	Republican	Elected in 1914. Retired to run for U.S. Senator.
March 4, 1917 – March 3, 1919	65th		William E. Mason	Republican	Elected in 1916. Re-elected in 1918. Re-elected in 1920. Died.		Medill McCormick	Republican	Elected in 1916. Retired to run for U.S. Senator.
March 4, 1919 – March 3, 1921	66th						Richard Yates Jr.	Republican	Elected in 1918. Re-elected in 1920. Re-elected in 1922. Re-elected in 1924. Re-elected in 1926. Re-elected in 1928. Re-elected in 1930. Lost re-election.
March 3, 1921 – June 16, 1921	67th
June 16, 1921 – November 7, 1922			Vacant
November 7, 1922 – March 3, 1923			Winnifred Huck	Republican	Elected to finish her father's term. Retired.
March 4, 1923 – March 3, 1925	68th		Henry R. Rathbone	Republican	Elected in 1922. Re-elected in 1924. Re-elected in 1926. Died.
March 4, 1925 – March 3, 1927	69th
March 4, 1927 – July 15, 1928	70th
July 15, 1928 – March 3, 1929			Vacant
March 4, 1929 – March 3, 1931	71st		Ruth H. McCormick	Republican	Elected in 1928. Retired to run for U.S. Senator.
March 4, 1931 – March 3, 1933	72nd		William H. Dieterich	Democratic	Elected in 1930. Retired to run for U.S. Senator.
March 4, 1933 – January 3, 1935	73rd		Martin A. Brennan	Democratic	Elected in 1932. Re-elected in 1934. [data unknown/missing]		Walter Nesbit	Democratic	Elected in 1932.[data unknown/missing]
January 3, 1935 – June 2, 1935	74th						Michael L. Igoe	Democratic	Elected in 1934. Resigned to become U.S. Attorney
June 2, 1935 – January 3, 1937							Vacant
January 3, 1937 – January 3, 1939	75th		Edwin V. Champion	Democratic	Elected in 1936. [data unknown/missing]		Lewis M. Long	Democratic	Elected in 1936. [data unknown/missing]
January 3, 1939 – January 3, 1941	76th		John C. Martin	Democratic	Elected in 1938. Retired.		Thomas V. Smith	Democratic	Elected in 1938. Lost re-election.
January 3, 1941 – January 3, 1943	77th		Stephen A. Day	Republican	Elected in 1940. Re-elected in 1942. Lost re-election.		William Stratton	Republican	Elected in 1940. Retired.
January 3, 1943 – January 3, 1945	78th
January 3, 1945 – January 3, 1947	79th		Emily T. Douglas	Democratic	Elected in 1944. Lost re-election.
January 3, 1947 – January 3, 1949	80th		William Stratton	Republican	Elected again in 1946. Retired.