President James Madison stationed a company of 100 militia on the grounds of the President's House. Camped on the North Lawn, the volunteers positioned a cannon at the North Gate, but retreated before the British entered Washington.

The Commissioner for Public Buildings, Joseph Elgar, recommended to President James Monroe that Monroe allow the President's House to be guarded. The men would be in plain clothes and serve as guides for visitors by day and protect the White House by night.

District of Columbia Marshal Tench Ringgold ordered guards posted at the gates and front doors to maintain order at the president's public levees.

During the Martin Van Buren administration, the White House grounds were patrolled by a day guard and a night watchman.

Establishment of the first permanent security force for the White House was an auxiliary guard that consisted of a captain and three other men. Their responsibilities were defined only loosely, but they often mingled with crowds at receptions, on the lookout for suspicious looking people, and kept an eye on callers who came to the White House to see the president.

Franklin Pierce became the first president to have a full-time bodyguard, Thomas O'Neil, who had worked for Pierce during Pierce's service in the Mexican War. Pierce introduced the two-level security arrangement that characterizes presidential protection today. A guarded outer perimeter securing the Executive Mansion itself, and an inner perimeter -- a bodyguard to protect the person of the president.

General Winfield Scott stationed almost 3500 soldiers in and around Washington to guard inaugural celebrations and the lives of President James Buchanan and President-elect Abraham Lincoln. Metropolitan Police guarded the Executive Mansion but Lincoln did not want the house to take on the characteristics of an armed camp. Guards inside the Executive Mansion (the doormen) dressed in civilian clothes and concealed their firearms. Uniformed, armed sentries were posted at the gates to the grounds and at the doors to the Executive Mansion itself.

There were heightened security fears in Washington that Confederates just across the Potomac in Virginia could easily slip across the river and attack President Lincoln at the White House. Ten soldiers were assigned to the White House as night guards.

The Frontier Guard of Kansas, a group of 65 to 70 volunteer soldiers, guarded the White House.

Company K of the 150th Pennsylvania Infantry Regiment known as the bucktails for the deer tail worn on their hats provided protection at the White House and the cottage at the Soldiers Home. The 11th New York Volunteer Cavalry accompanied Lincoln as he traveled between the White House and the Soldiers Home until a unit specifically created for this purpose, the Union Light Guard of Ohio, provided the cavalry escort.

Following a request from District of Columbia U.S. Marshal Ward Hill Lamon, who was a close friend of Lincoln and who guarded him whenever possible, four to five men from the D.C. Metropolitan Police were assigned to guard the White House and protect the president. These men included John Cronin, Alphonso Dunn, Andrew Smith and Thomas Pendel.

Mounted artillery, cavalry, 140 soldiers, and a few D.C. police officers were assigned to guard the White House while gravely wounded President James Garfield was convalescent there.

An intruder climbed onto the South Portico and into the Red Room; he was restrained and held down by guards and President Benjamin Harrison.

Grover Cleveland began his second term as president. First Lady Frances Folsom Cleveland and President Cleveland's private secretary Henry T. Thurber were worried about threats to President Cleveland's life.

The White House grounds were totally closed to shield the Cleveland's young daughters Ruth and Esther. Over-eager tourists had hugged and kissed Ruth and one even tried to snip off some of her hair.

Worried about the march of Coxey's Army of the unemployed, and the violence accompanying the Pullman railroad strike, Thurber worked with the Metropolitan Police superintendent to increase the D.C. Metropolitan Police's White House detail to 34, and secured approval from Treasury Secretary John G. Carlisle for the Secret Service to begin informal, part-time protection of Cleveland.

A new sentry box was placed directly in front of the White House main door. Some newspapers criticized the box because it made it seem as though the White House off limits, but Thurber said it was merely to keep the guards warm on cold nights.

In response to security concerns caused by the Spanish-American War, White House guards were assigned to three shifts of eight hours apiece. More lamp posts were added for night security. The police who guarded the inside of the White House were placed under the direct command of President William McKinley's private secretary, John Addison Porter.

After the assassination of President McKinley, Congress informally requested Secret Service protection for the president.

Congress passed the Sundry Civil Expenses Act for 1907, providing funds for Presidential protection by the Secret Service.

During the Theodore Roosevelt administration, the Secret Service assumed full-time responsibility for protecting the president. President Roosevelt was guarded by at least two Secret Service men. President Roosevelt wrote Senator Henry Cabot Lodge in 1906: "The secret service men are a very small but very necessary thorn in the flesh."

The Secret Service began protecting the president-elect.

Responding to security concerns surrounding World War I, Congress permitted permanent protection of the presidents immediate family.

At the request of President Warren G. Harding, a permanent, separate White House Police Force was created.

The White House Police Force was placed under the administration of the Secret Service.

Congress passed Public Law 82-79, which permanently authorized Secret Service protection of the president, his immediate family, the president-elect, and the vice president.

Congress passed Public Law 87-829, enlarging Secret Service coverage to include the vice president (or the next officer to succeed the president) and the vice president-elect.

Congress passed Public Law 90-331, authorizing protection of major presidential and vice presidential candidates and nominees, and of widows of presidents until death, or remarriage, and their children until age 16.

Congress passed Public Law 91-217, renaming the White House Police Force the Executive Protective Service.

The Executive Protective Service was officially renamed the Secret Service Uniformed Division.

Congress passed Public Law 103-329, authorizing Presidents elected to office after January 1, 1997 to receive Secret Service protection for 10 years after leaving office. Individuals elected to office prior to January 1, 1997, would continue to receive lifetime protection.

In accordance with Public Law 107-296, passed in November 2002, the U.S. Secret Service was transferred from the Department of the Treasury to the Department of Homeland Security.