Why King Charles and Other Senior Royals Are Still Wearing the Queen's Cypher on Military Uniforms

King Charles III and Prince William, Prince of Wales
King Charles III and Prince William, Prince of Wales

Toby Melville - WPA Pool/Getty; Samir Hussein/WireImage

The legacy of Queen Elizabeth lives on.

Senior members of the royal family stepped out in London Sunday for the National Service of Remembrance at the Cenotaph war memorial, where the late Queen's cypher was visible on their military uniforms. As seen on the dress coats of King Charles III, Prince William and Prince Edward across their respective regiments, interlocking "ERII" insignia pins remained on their left shoulders.

Charles, 74, immediately acceded as King upon his mother's death on Sept. 8, thus becoming Commander-in-Chief of the British Armed Forces. Though courtiers created a new cypher in his honor soon after, Queen Elizabeth's ERII emblem will remain on the uniforms of military personnel for the time being, The Telegraph reports. According to the outlet, Charles' new insignia will replace his mother's only when uniforms need to be replaced and the existing stock of "badges, buttons and insignia" runs out.

King Charles III and Prince William, Prince of Wales
King Charles III and Prince William, Prince of Wales

Samir Hussein/WireImage

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"At next year's Cenotaph service, and for years to come, some military personnel will be wearing the King's cypher while others will still be wearing the late Queen's," the newspaper notes. "A spokesman for the Ministry of Defence said that the switch to the King's cypher will be a gradual one, with individual regiments and other military units introducing it in their own time."

Unlike her brothers and nephew, Princess Anne did not wear the Queen's insignia; the emblem was not part of her Royal Navy uniform at Queen Elizabeth's state funeral on Sept. 19.

Princess Anne, Prince Edward, Earl of Wessex
Princess Anne, Prince Edward, Earl of Wessex

Samir Hussein/WireImage (2)

Much like Queen Elizabeth's cypher, King Charles' emblem features the crown above his first initial "C," intertwined with an "R" for Rex. Latin for "King," Rex or Regina (for "Queen") has traditionally been used for the monarch dating back to the 12th century. Charles' regnal number "III" is tucked inside the "R," while Elizabeth's regnal number "II" separated the "E" and the "R."

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The King's New Cypher
The King's New Cypher

Yui Mok - Pool/Getty

Charles' cypher will eventually become commonplace where royal symbols are shown, with the symbol stamping postmarks on all mail leaving Buckingham Palace since late September. The cypher will also be seen on state documents and eventually on the familiar red mailboxes around the U.K., as well as used by U.K. government departments on their mail.

The new cypher is King Charles' personal property. He chose the design from several that were created by the palace's heraldry experts, the College of Arms.