The East wing floor plan was primarily designed as an entrance for large social gatherings. A significant reason for this was the space to park cars and carriages. The cloakroom was another reason why it was used as an entrance.
After 1942, the coatroom turned into a movie theatre, and many crucial offices like calligraphers and social secretary were set up there. It also has the Presidential Emergency Operations Center.
Since 1977, the white house east wing floor plan was changed to accommodate the first lady's office and staff. The first lady is aided by the social secretaries to prepare invitations for social events and correspondence. Other than this, there is a garden room, family theatre, and the visitor's Foyer.
https://www.edrawsoft.com/article/white-house-floor-plan.html
For the FLOTUS social team, no two days in the office are alike. As a team of four, these women work closely with the First Lady and Social Secretary to manage the production and logistics of all events for the Executive Residence of the White House. These events can range from informal meetings involving President Obama to large-scale productions like the State Dinner.
https://theeverygirl.com/working-at-the-white-house-meet-the-women-of-the-flotus-office-part-1
The most noteworthy use of the PEOC was on September 11, 2001. Though President George W. Bush was in Florida at the time of the terrorist attacks, Vice President Dick Cheney and several other high ranking officials were evacuated from their offices in the White House to the PEOC. Pictures of that time, from within the PEOC, have been released by the U.S. National Archives.
The first White House bunker was built during the Second World War in order to protect President Franklin D. Roosevelt in the event of aerial attacks on Washington.The modern PEOC, which resides under the East Wing of the White House, has been updated continuously. Notably, it received a construction overhaul as part of renovation work done in 1950 at the time of President Harry S. Truman's presidency. During Truman's presidency, the bunker had to be adapted for the new threat of nuclear war and was likely constructed deeper into the ground than its predecessor.
Every day, the PEOC is manned around the clock by joint-service military officers and non-commissioned officers. The modern PEOC is equipped with state-of-the-art communications equipment that allows the President to communicate with government officials outside.
https://interestingengineering.com/a-look-inside-the-us-presidents-top-secret-white-house-bunker
Chief White House Calligrapher Pat Blair (foreground) spoke about the calligraphy office's operations as they prepared invitations for a state dinner for Queen Elizabeth II. She also talked about the daily operations of the office and printing official correspondence, invitations, and other special documents. Pat served as president of the Washington Caligraphers Guild 2001-03. Pictured in rear is calligrapher Debra Brown.
Converted from a cloakroom in 1942 on the orders of Franklin Roosevelt (the 32nd President of the USA) the room was originally called the Hat Box in it's first guise as a cloakroom. Prior to this there was no screening room for watching movies and film viewings were set up temporarily in the main building.
There are 42 seats in the home theatre which was renovated with the help of the motion picture industry through the 1980's and then during George W. Bush's Presidency redecorated in it's current "movie palace red".
trivia:President Kennedy watched ‘From Russia with Love' the night before he was killed
