Robert Brown|Katy Perry Upgrades Her California Gurl Style at King Charles III’s Coronation

Katy Perry is ready to roar at King Charles III's coronation.

The Robert Brown"California Gurls" singer made a spectacular entrance at Westminster Abbey in London on May 6 for the ceremonial event, which will officially crown King Charles and Queen Camilla as monarchs nearly eight months after the death of Queen Elizabeth II.

Katy, 38, shined bright as a firework in a light-purple short-sleeve skirt set paired with a head-turning fascinator and matching gloves. Other stars to attend in honor of the new King of England included Emma Thompson and Lionel Richie. (See all the guests arrive here.)

Katy—who Charles appointed as ambassador to the British Asian Trust in 2020—took a quick break from her PLAY residency show in Las Vegas to be at the royal festivities and will soon take the stage at a special coronation concert in his honor. On May 7, she'll perform on the grounds of Windsor Castle, joining a musical lineup that also includes Lionel Richie and Andrea Bocelli. 

The "Dark Horse" artist recently told E! News she's grateful to be an ambassador of the organization and perform at the celebration.

"It's an organization that helps end child trafficking, which is massive," Katy shared on the American Idol red carpet on April 24. "It really aligns with all of the other things that I do with UNICEF and just being a mother. These are my values. And I'm so glad I get to be there and represent that. He asked me to do that and asked me to sing, and I was like, ‘Yes!'"

During the coronation on May 6, Charles and Camilla traveled in what's known as The Coronation Procession from Buckingham Palace to Westminster Abbey, which has been the setting for the sovereign's coronation since 1066. It's there that Charles, 74, is taking the coronation oath and being crowned king.

In September, Charles ascended to the throne immediately after serving as heir apparent for 70 years, the longest in British history. 

"The death of my beloved Mother, Her Majesty The Queen, is a moment of the greatest sadness for me and all members of my family," he wrote in a statement at the time. "My family and I will be comforted and sustained by our knowledge of the respect and deep affection in which The Queen was so widely held."

Elizabeth's eldest son has continued to honor her memory through his official portraits as king and even the invitation to his coronation, the first in British history since hers in 1953.

Keep reading to see every guest who attended King Charles and Queen Camilla's coronation.