Today the Irish Crown Jewels would be valued at several million euro. The jewels were discovered to be missing on 6 July 1907. The Times reported that 'there is no spot in Dublin, or possibly in the UK, which is at all hours of the 24 more constantly and systematically occupied by soldiers and policemen.

The most famous theft in the history of Dublin Castle occurred on July 6, 1907, when the Irish Crown Jewels were discovered missing from the Bedford Tower. These "jewels" were not part of the British monarchy's regalia but were the insignia of the Most Illustrious Order of St. Patrick, consisting of a diamond-encrusted star, a diamond badge, and five gold collars of the Order. The theft was a massive international scandal, particularly because it occurred just days before a royal visit by King Edward VII and took place within a heavily fortified castle guarded by soldiers and police. Despite a massive investigation and the dismissal of the Ulster King of Arms, Sir Arthur Vicars, the jewels were never recovered. The case remains one of Ireland's greatest unsolved mysteries, with theories ranging from an "inside job" by disgruntled staff to a complex conspiracy involving Unionists or even a high-society "gentleman thief" like Francis Shackleton.