title: List of monarchs in Britain by length of reign
context: Queen Elizabeth II became the longest-reigning British monarch on 9 September 2015 when she surpassed the reign of her great-great-grandmother Victoria.[1][2] On 6 February 2017 she became the first British monarch to celebrate a Sapphire Jubilee, commemorating 65 years on the throne.
question: Which English monarch has had the longest reign?
answers: Queen Elizabeth II