Congress fixes the size of the House of Representatives, and the procedure for apportioning the number of Representatives among the States, and the States themselves proceed from there. State legislatures pass laws defining the physical boundaries of congressional districts, within certain constraints established by Congress and the Supreme Court. Each State is apportioned its number of Representatives by means of the Department of Commerce's decennial census. In the very early years of the Republic, most States elected their Representatives at large. The practice of dividing a State into districts, however, was soon instituted. The redistricting process has always been provided for by State law, but Congress can choose to exercise greater authority over redistricting. In 1967, for example, Congress by law prohibited at large elections of Representatives in all States entitled to more than one Representative. Today, all States with more than one Representative must elect their Representatives from single
