The United Kingdom has a new Monarch.
During the ceremony, King Charles made a declaration and swore under oath in the presence of privy counsellors, including Queen Consort, Camilla, and his oldest son, William, who is now the Prince of Wales.
"My mother's reign was unequalled in its duration, its dedication and its devotion," Charles said, per NBC News. "Even as we grieve we give thanks for this most faithful life. I am deeply aware of this great inheritance and of the duties and heavy responsibilities of sovereignty which have now passed to me."
Traditionally, an accession council is held within 24 hours of a monarch's death. However, King Charles III still received his new title immediately after the Queen passed away on Sept. 8.
That day, the royal family announced in a statement on Twitter that the monarch "died peacefully" at her Balmoral estate in Scotland.
Following Her Majesty's death, the King declared a period of royal mourning, which is set to last until seven days after his mother's funeral, which does not yet have a date set.
In his first speech as sovereign, the King paid a heartfelt tribute to his late mother, who he watched lead for 70 years as the longest-reigning British monarch.
"To my darling Mama, as you begin your last great journey to join my dear late Papa, I want simply to say this: Thank you," Charles said in a pre-recorded address Sept. 9. "Thank you for your love and devotion to our family and to the family of nations you have served so diligently all these years. May 'flights of Angels sing thee to thy rest.'"
He added, "Throughout her life, Her Majesty The Queen—my beloved Mother—was an inspiration and example to me and to all my family, and we owe her the most heartfelt debt any family can owe to their mother; for her love, affection, guidance, understanding and example. Queen Elizabeth was a life well lived; a promise with destiny kept and she is mourned most deeply in her passing. That promise of lifelong service I renew to you all today."
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