At age 25, Elizabeth II became Britain's 40th monarch and vowed to dedicate her life to service and duty on behalf of her country. She is the constitutional monarch of 16 sovereign states, head of the 53 member Commonwealth of Nations, Supreme Governor of the Church of England, and head of the armed forces. Most notably, however, on September 9th, 2015, she became the longest reigning monarch in British history. She has consistently adapted in order to remain relevant, while devotedly upholding the age-old traditions of the monarchy.

Although there have only been six British female monarchs, it cannot be argued that some of the most enlightened times in history have occurred during periods of queenship. Elizabeth I led the country through the Golden Age and Victoria ushered in the Industrial Revolution, but it is Elizabeth II who will leave the most illustrious and progressive legacy of all.

CNN Royal Contributor, Victoria Arbiter, has spent a lifetime in direct contact with the Royal Family. From her earliest memories as the daughter of a former Press Secretary to HM the Queen, to her live coverage of 2012's Diamond Jubilee celebrations for ABC News and the previous year's Royal Welling for CBS News, Victoria has a unique perspective on the British monarchy. Combining extensive knowledge with sharp British wit, Arbiter's approach reveals the Royal Family in a way that entertains as much as it informs. As a result, she was personally invited by Barbara Walters to contribute to two prime-time documentaries for ABC, and she was a guest during the final season of the Opray Winfrey Show. In addition to her reporting for CBS, ABC and CNN, Victoria is a regular contributor to Entertainment Tonight, The Katie Show, CTV (Canada), Channel 7 (Australia), BBC World and ITV (UK). She writes a regular blog for CNN.com and has been featured in numerous international publications.