The building at 1600 Pennsylvania Avenue was completed in 1800 and originally called the President’s Palace. In 1810, its name was officially changed to the Executive Mansion to avoid regal connotations. It wasn’t until Theodore Roosevelt’s era that the structure began to be referred to as the White House. The nickname first appeared around 1811, supported by an April 24 letter from British diplomat Francis J. Jackson to former Secretary of State Timothy Pickering, noting the building’s white-gray exterior that stood out among nearby red-brick houses. Although popular informally, the formal designation did not take hold until 1901, about a month after Roosevelt assumed office. A letter dated October 17, written by the president’s private secretary, George B. Cortelyou, instructed officials to replace references from “Executive Mansion” to “White House” on official papers, signaling a modernization effort. Roosevelt’s Presidential Library confirms that this name change aimed to present the presidency as a symbol of the people rather than a private residence.