From DC North, November 2003:

Two large rural tracts were combined to make the Petworth subdivision, one of the city's largest and earliest suburban subdivisions. In October, 1886, a real estate syndicate paid $260 per acre for the 183-acre country estate of Marshall Brown. A separate syndicate, though with some of the same members, then purchased the adjacent Petworth estate. Half of Petworth was purchased in early 1887, the other half in June 1888, both from heirs of Washington's famous Tayloe family. In all, Petworth's 204 acres sold for about $1,100 per acre.

The Petworth estate was, with the exception of the famous Octagon House at New York Avenue and 18th Street, the last large property in the District belonging to the heirs of Colonel John Tayloe, the city's wealthiest resident in its early days. Col. Tayloe built the Octagon, now a museum, for his own residence, as well as the building which eventually housed the original Willard Hotel, on Pennsylvania Avenue at 14th Street. Tayloe purchased the Petworth land in about 1803. An avid horseman, Tayloe founded the Jockey Club, "kept a stable of fine thoroughbred animals and…had a track laid out on his Petworth farm," according to one Washington history writer.

Both of the Petworth syndicates included B. H. Warner, B. H. Warder, and E. A. Paul. Brainard H. Warner came to Washington as a teenager to help the Union cause during the Civil War. He began his real estate business in 1869, and in 1890 founded Kensington, Maryland, where he kept a summer home. A 1902 publication by The Washington Post includes the following description of B. H. Warner: "Mr. Warner has probably had a more active career in reference to the formation of associations, companies and corporations than any other citizen of the District of Columbia. For nearly thirty years he has been connected with every important public project in some capacity."

The Petworth subdivision was recorded at the city's surveyor's office on January 16, 1889. The streets were laid out as an extension of L'Enfant's plan for the original City of Washington (south of Florida Avenue.) The developers took the unusual step of adding diagonal State streets (Illinois, Kansas, and the extension of New Hampshire), and Petworth is one of the few places outside of the Old City with large traffic circles (Grant and Sherman) where the diagonal avenues cross.

The Petworth subdivision lies between Second Street on the east, Rock Creek Church Road on the south, Georgia Avenue on the west, and Hamilton Street on the north. The developers (the syndicates that purchased the land) spent $40,000 to prepare the southernmost 50 acres of the subdivision for residents. It was expected that $200,000 would be spent for the entire 387-acre subdivision.

On October 18, 1888, congress authorized the Brightwood Railway Company to build a streetcar line on Georgia Avenue (then known as Seventh Street Extended or Brightwood Avenue) from Florida Avenue (Boundary Street) to the District line at Silver Spring. The Brightwood Railway Company might just as well have been called the Petworth Railway Company, as at least four of the five founders were partners in Petworth, including the line's president, A. A. Thomas.

The Metropolitan Railroad Company had run a horse-drawn line on Georgia Avenue to Rock Creek Church Road since about 1873. The Metropolitan was authorized to run the streetcar line all the way to the District boundary, but the area was sparsely developed and the horsedrawn cars offered a long, slow trip to and from the city. Business was slow. Congress apparently thought that the men who were investing in such a large subdivision as Petworth could make the streetcar line successful. The Brightwood Railway Company bought the Metropolitan's Georgia Avenue line in 1890 and electrified it. The streetcar line provided the only regular transportation between the new "bedroom community" of Petworth and the employment, shopping, and cultural opportunities of the city.

Despite improvements made to the area, sales and development were slow. The 1893-1894 tax assessment shows that no lots were sold and only three houses were erected. The developers sold much of Petworth to Horace S. Cummings in the mid-1890s for a reported $2,500 per acre. Many blocks of the undeveloped subdivision were owned by The Washington Loan & Trust Company, which had been founded by B. H. Warner in 1889. The Petworth Syndicate gave up on development in the northern part of the subdivision for a while and created the Columbia Golf Club in 1898.

There was no substantial development of Petworth until after 1900. Development before and around that time occurred mostly at the southern edge of the Petworth subdivision and consisted mainly of detached houses. Slowly, developers began to build duplexes and rowhouses as demand for housing increased.

A housing shortage in the early 1920s sent developers into overdrive, building high-density housing throughout the district. Petworth was rapidly built-up with long chains of rowhouses and apartment houses and stores along Georgia Avenue. Dozens of developers were active in Petworth in the 1910s and 1920s, but chief among them was Morris Cafritz, who built hundreds of rowhouses in Petworth in the mid-1920s.

Through time, the Petworth name extended beyond the original subdivision, and was also used for the area across Georgia Avenue as far west as Sixteenth Street. The 1930 census, recorded just after the building boom in Petworth, recorded only about 1% "Negro" residents in the larger Petworth area. Many of the first residents in Petworth's rowhouses were Jewish families who had moved from Southwest and Downtown. By 1950, there were several dozen African American households in Petworth, most in the far southern part of the neighborhood, near Spring Road and Rock Creek Church Road.

The 1950s brought school desegregation and tremendous demographic change to Petworth. The 1960 census recorded about 77 percent of households in Petworth as being "non-white." By 1980 Petworth was practically an exclusively African American community. The white population was only 3%. The third largest group was persons of "Spanish origin," with 1.4 percent of the population. The trend of Latino families, mostly immigrants from Central America, moving to Petworth increased in the 1980s and 1990s.

Construction of Metro's Green Line, beginning in 1994, brought turmoil and devastation to the south end of Petworth. Although Mayor Sharon Pratt Kelly pressured Metro to adopt a plan that would minimize the loss of houses, the noise and dirt, the detouring of traffic, and the loss of commercial businesses proved to be an ordeal for the community. The Georgia Avenue-Petworth station, at Georgia and New Hampshire Avenues, opened in January of 2001.