History of the Architect of the Capitol

The Architect of the Capitol's origins date to the founding of the federal capital.

The Architect of the Capitol is both the name of the U.S. legislative branch agency responsible for the maintenance and upkeep of the Capitol campus, as well as the title for the leader of the agency. 

1790-1800

The AOC's origins date to the nation's early years and the founding of the federal capital. The Residence Act of 1790 established Washington, D.C., as the seat of the national government and authorized a Board of Commissioners to "provide suitable buildings for the accommodation of Congress." The commissioner hired Pierre Charles L'Enfant to develop a city plan and Andrew Ellicott to survey the boundaries of the 100-square-mile federal district.

In 1792, Dr. William Thornton's depiction of a grand, two-winged structure topped by a central dome won a public competition for the design of the U.S. Capitol Building (U.S. Capitol). Today, Thornton is credited as the first "Architect of the Capitol." Construction of the U.S. Capitol began when President George Washington set the building's cornerstone in 1793, and seven years later, in 1800, Congress convened in the building for the first time.

1801-1900

In 1802, Congress consolidated the duties of the Board of Commissioners into a single superintendent, the Commissioner of Public Buildings and Grounds, with the responsibility for the care of the U.S. Capitol, which at the time housed Congress, the Library of Congress, the Supreme Court, the district courts and other offices and the U.S. Capitol Grounds. Following the 1814 burning of the U.S. Capitol by British troops, the building was restored and expanded to accommodate the needs of a growing Congress.

During the 1850s and 1860s, a new position, the Architect of the Capitol Extension, oversaw the cast-iron dome construction and the addition of the north and south extensions to the building. The artist Constantino Brumidi's murals, painted between 1855 and 1880, contributed to the U.S. Capitol's beauty and unique symbolic character. In 1867, Congress combined the responsibilities of the Commissioner of Public Buildings and Grounds with those of the Architect of the Capitol Extension. Between 1874 and 1892, the grounds surrounding the U.S. Capitol expanded based on the visionary design of American landscape architect Frederick Law Olmsted.

During this period, in 1876, Congress established the Architect of the Capitol as a permanent office under the legislative branch of the federal government.

1901 - 2000

As the size of the Capitol campus continued to expand, so did the AOC's mission and responsibilities. During the 20th century, the agency assumed responsibility for the operation, maintenance and preservation of the Library of Congress' Thomas Jefferson Building and the U.S. Botanic Garden (USBG). The AOC also oversaw new construction on Capitol Hill to support the expanding needs of Congress, the Supreme Court and the Library of Congress. During this period, the AOC managed the construction of three House office buildings, three Senate office buildings, the Supreme Court of the United States, the Thurgood Marshall Federal Judiciary Building, the Library of Congress' John Adams Building and James Madison Memorial Building, the Capitol Power Plant's generator building and main boiler plant and other support facilities. The U.S. Capitol was named a National Historic Landmark in 1960. In 2000, a symbolic groundbreaking initiated the construction of the U.S. Capitol Visitor Center (CVC).

2001 - Present

The 21st century began with the construction of the CVC, which was completed and opened to the public in 2008. The addition of the CVC marked the largest expansion of the U.S. Capitol and significantly enhanced the security, safety, comfort and educational experience of its visitors. In 2011, the AOC received responsibility for Union Square, a 13-acre site between the U.S. Capitol and the National Mall, which increased the agency's stewardship land responsibility to more than 570 acres. In 2017, Congress transferred responsibility for the O'Neill House Office Building to the AOC. In 2018, the agency completed construction on the Cogeneration Plant at the Capitol Power Plant. Currently, the AOC is conducting a wide range of building, facility and infrastructure restoration and renewal projects across the Capitol campus.