Edward Clark was appointed Architect of the Capitol Extension in 1865 by President Andrew Johnson to fill the vacancy caused by Thomas U. Walter’s resignation. Under way for over 14 years, the interior of the U.S. Capitol extension was at this point complete, and only the outside porticoes needed to be finished.
In 1867, with the completion of the Capitol Building’s extension fast approaching, Congress directed Clark to take over the Capitol-related responsibilities formerly held by the commissioner of public buildings. Thus, he would take responsibility for the care and maintenance of the Capitol and its grounds. Clark’s title soon changed to Architect of the Capitol, dropping the word "Extension" to reflect the broader responsibilities of the new office. Clark is considered the first Architect of the Capitol as the term refers to the head of a congressional agency.
Born in Philadelphia in 1822, Clark came to Washington as an architectural student in Walter’s office and served in various capacities during his master’s tenure. In his own term he completed the Capitol extension and new dome projects and oversaw the construction of the western terraces that were designed by the landscape architect Frederick Law Olmsted. Also during his administration, the Library of Congress moved to its own building, and the west central interior of the Capitol was reconstructed. Clark died in 1902 while still in office.