On this day in history, Massachusetts Governor Elbridge Gerry signed an electoral redistricting law that would favor his political party. (His party, then called the Democratic-Republican Party, the Republican Party or the Jeffersonian Republicans, opposed the strong central government policies of the Federalist Party.)
The Boston Gazette caricatured the tactic on March 26, 1812 with the cartoon shown below of the resulting district in Essex County, Massachusetts, declaring that the shape resembled a salamander. The practice of redrawing voting districts for political advantage was labeled by the Gazette as “gerrymandering,” which was a portmanteau of the governor’s last name and the word salamander.
For the remainder of 1812, the word gerrymander was reprinted numerous times in Federalist newspapers across the country. Gerrymandering soon began to be used to describe not only the original Massachusetts example, but also other cases of district-shape manipulation for partisan gain in other states. [Since the letter g of the eponymous Gerry is pronounced as a hard g, as in go, the word gerrymander was originally also pronounced with a hard g. Through common usage, however, pronunciation with a soft g, sounding like j, has become the accepted pronunciation.]
Gerrymandering is still a popular practice, most recently used to try to hinder particular racial or ethnic minorities from winning legislative seats.
For much more information on gerrymandering, and especially on modern usages, the Library of Congress has a great deal of information.