legislative apportionment, subdivision of a political body (e.g., a state or province) for the purpose of electing legislative representatives. In the United States, the Constitution requires that Congressional representatives be elected on the basis of population. State legislatures, not bound by the constitutional strictures, were apportioned according to considerations including population, as well as geographic size, special interests, and political divisions such as counties or towns. This often resulted in unrepresentative, minority control of the state legislature. The state legislatures were responsible for drawing up districts for the purpose of electing representatives to Congress. Gerrymandering often resulted (see gerrymander gerrymander (jĕr`ēmăn'dər, gĕr–)
..... Click the link for more information. ). In some states legislatures did not redistrict, despite population shifts, for as many as sixty years. This was the case until 1962 when the U.S. Supreme Court ruled in Baker v. Carr Baker v. Carr, case decided in 1962 by the U.S. Supreme Court. Tennessee had failed to reapportion the state legislature for 60 years despite population growth and redistribution.
..... Click the link for more information. that a voter could challenge legislative apportionment on the grounds that it violated the equal protection clause of the Fourteenth Amendment to the Constitution. Within nine months of the decision suits for reapportionment were brought in at least 34 states. In 1964, in Reynolds v. Sims, the Supreme Court ruled that population, i.e., the one-person, one-vote principle, must be the primary consideration in apportionment plans for both houses of state legislatures.

legislative apportionment

or legislative delimitation

Process by which representation is distributed among the constituencies of a representative assembly. In ancient Athens, every citizen represented himself, but throughout most of history representation has been restricted to certain social classes. With the growth of democracy, the extension of suffrage, and the rise of political parties, apportionment had to be methodically and mathematically arranged to ensure that the distribution of legislative seats would most accurately reflect the electorate's will. Territorial apportionment is currently the most common form. See also gerrymandering, proportional representation.