Context: Elizabeth's many historic visits and meetings include a state visit to the Republic of Ireland and reciprocal visits to and from the Pope. She has seen major constitutional changes, such as devolution in the United Kingdom, Canadian patriation, and the decolonisation of Africa. She has also reigned through various wars and conflicts involving many of her realms. She is the world's oldest reigning monarch as well as Britain's longest-lived. In 2015, she surpassed the reign of her great-great-grandmother, Queen Victoria, to become the longest-reigning British head of state and the longest-reigning queen regnant in world history.

Question: Who is the world's oldest reigning monarch?
Answer: Elizabeth

Question: Than which queen has Elizabeth ruled longer?
Answer: Queen Victoria

Question: How is Victoria related to Elizabeth?
Answer: great-great-grandmother

Question: In what year did Elizabeth pass Victoria's length of rule?
Answer: 2015

Question: In the history of what is Elizabeth the longest reigning queen?
Answer: world history

Question: What was the last year that Elizabeth did a state visit in the Republic of Ireland?
Answer: Unanswerable

Question: When was the last year Elizabeth traveled to the Vatican to visit the Pope?
Answer: Unanswerable

Question: Who had the shortest reign on the British throne?
Answer: Unanswerable

Question: When was the last year the Pope traveled to England to meet Elizabeth?
Answer: Unanswerable

Question: Who became Queen of England at the youngest age?
Answer: Unanswerable