United States v. Lee (1882)
With local cemeteries in Alexandria County and Alexandria filling rapidly with war dead, Quartermaster General of the United States Army Montgomery C. Meigs proposed using of the Arlington estate as a cemetery. The first burial there was made on May 13, 1864. United States Secretary of War Edwin M. Stanton approved the establishment of a military cemetery on June 15, 1864, creating Arlington National Cemetery. By the end of the war in April 1865, more than 16,000 people had been buried at Arlington. In September 1866, a memorial and a burial vault (containing the remains of 2,111 U.S. and Confederate soldiers who died at the First Battle of Bull Run, Second Battle of Bull Run, and along the Rappahannock River) were buried in Lee's former wildflower garden on the mansion's east side beneath the Civil War Unknowns Monument, a memorial to honor unknown soldiers who had died during the American Civil War.
John C. Metzler Jr.
In 2007, Metzler implemented the Millennium Project, a $35 million, 100-year-long expansion plan which transferred of woodland from the National Park Service-controlled Arlington House and from adjacent Fort Myer to the cemetery. Another of cemetery property currently occupied by maintenance buildings would also be converted to burial space. The expansion would add 14,000 burial and 22,000 inurnment spaces. The Millennium Project expanded Arlington's physical boundaries for the first time since the 1960s, and this was the largest expansion of burial space at the site since American Civil War. Metzler also implemented plans move several utility lines to gain even more space. Metzler's plans were criticized and opposed by several environmental and historical preservation groups.