Apportionment Legislation 1890 - Present
An Act Providing for Apportionment following the 1890 Census (February 7, 1891)
Increased the size of the House of Representatives to 356 seats. These seats were apportioned among the states using the Webster and Hamilton/Vinton Methods, which agree at this chamber size.
An Act Providing for Apportionment following the 1900 Census (January 16, 1901)
Increased the size of the House of Representatives to 386 seats.
An Act Fixing the Size of the House of Representatives (August 8, 1911)
Sets the size of the House of Representatives at 433 seats, with an additional one seat each allowed for the soon-to-be-states of Arizona and New Mexico, when they were admitted into the Union.
Reapportionment and Census Act of 1929 (June 18, 1929) and The Act Providing for the Fifteenth Census and for the Apportionment of Representatives in Congress
After Congress, dominated by rural politicians who stood to lose clout in a quickly urbanizing nation, failed to reapportion its seats following the 1920 census, this law set the process in place so that apportionment would occur automatically following the 1930 enumeration. The size of the House remained at 435 seats.
An Act Providing for Apportionment following the 1940 Census (April 25, 1940)
Made reapportionment of the House of Representatives automatic, using the same method as the previous apportionment, unless Congress intervenes.
An Act Setting the Apportionment Method for Future Censuses (November 15, 1941)
Provided for the automatic reapportionment of the House of Representative's 435 seats following each census, using the Huntington-Hill/Equal Proportions Method.