It is adjacent to the newly built, four-lane, 2-mile-long (3.2 km) Harry W. Nice Memorial Bridge carrying U.S. Highway 301 over the Potomac River.

[3] It was substantially reorganized in 1776 and 1777, with land swapped with both Stafford and Westmoreland counties to form the modern boundaries.

In the early decades, planters cultivated tobacco, a labor-intensive commodity crop, depending on the labor of both indentured servants from Britain and enslaved Africans.

On March 16, 1751, James Madison, the fourth President of the United States, was born at Belle Grove plantation, the childhood home of his mother, Eleanor Rose "Nellie" Conway.

On May 1, 1861, during the American Civil War, Confederates installed artillery at Mathias Point in order to blockade the Potomac River.

On June 27, the steamer Thomas Freeborn bombarded Mathias Point in an effort to drive away the soldiers who were manning the weapons.

Confederate soldiers fired back from Mathias Point, striking and mortally wounding Commander James H. Ward of the Freeborn.

After assassinating President Abraham Lincoln, John Wilkes Booth and David Herold tried to elude Union cavalry and crossed into the Virginia county by boat from Maryland on April 21, 1865.

Booth and Herold landed at the mouth of Gambo Creek, before meeting with Confederate agents, who guided their passage to Port Conway.

King George is represented by Republican Richard Stuart in the Virginia Senate, Republican Hillary Pugh Kent in the Virginia House of Delegates, and Democrat Eugene Vindman in the U.S. House of Representatives.