Beatrice, the oldest daughter of Prince Andrew and Sarah Ferguson, wed Edoardo Mapelli Mozzi on Friday morning at the Royal Chapel of All Saints at Royal Lodge, Windsor, a Buckingham Palace spokesperson confirmed to ABC News.
The small ceremony was attended by Beatrice's grandparents, Queen Elizabeth and Prince Philip, and "close family," according to the spokesperson.
Buckingham Palace did not confirm whether Beatrice's parents and sister, Princess Eugenie, attended the wedding. Her father, Prince Andrew, continues to face intense scrutiny over his relationship with convicted sex offender Jeffrey Epstein, who died in prison from an apparent suicide last year.
Andrew announced last November he would step back from public duties "for the foreseeable future" amid heavy criticism.
Friday's wedding, which the Buckingham Palace spokesperson said "took place in accordance with all relevant Government Guidelines," was a much different affair than was originally planned by Beatrice and Mozzi, described by the BBC as a "property tycoon."
The couple, who got engaged last year in Italy, planned to wed on May 29 at the Chapel Royal at St. James's Palace in London, where Prince George, the son of Beatrice's cousin Prince William and his wife Kate, was baptized in 2013.
A private reception hosted by Queen Elizabeth was to follow the ceremony at Buckingham Palace's gardens.
Beatrice's mom, Sarah Ferguson, took to social media on May 29 to mark what would have been her oldest daughter's wedding day.
"Love you my darling Beatrice," Ferguson wrote on Instagram and Twitter, alongside a throwback photo of a young Beatrice. "You have given me more joy than I could ever wish for. I am so excited to celebrate yours and Edo’s love when we all are out of lockdown."
"The most important thing is health and love and today I send it to you and all the other people that were getting married during this time .. so proud of you all," she wrote.