You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

what is the first event mentioned?, Context: The Russian Revolution is the series of revolutions in Russia in 1917, which destroyed the Tsarist autocracy and led to the creation of the Soviet Union. Following the abdication of Nicholas II of Russia, the Russian Provisional Government was established. In October 1917, a red faction revolution occurred in which the Red Guard, armed groups of workers and deserting soldiers directed by the Bolshevik Party, seized control of Saint Petersburg (then known as Petrograd) and began an immediate armed takeover of cities and villages throughout the former Russian Empire.
Solution: Russian Revolution
Why? This is a good example, and the Russian Revolution is the first event mentioned.

New input: Who was in charge of St Peter, Context: The abbey was restored to the Benedictines under the Catholic Mary I of England, but they were again ejected under Elizabeth I in 1559. In 1560, Elizabeth re-established Westminster as a "Royal Peculiar" – a church of the Church of England responsible directly to the Sovereign, rather than to a diocesan bishop – and made it the Collegiate Church of St Peter (that is, a non-cathedral church with an attached chapter of canons, headed by a dean.) The last of Mary's abbots was made the first dean.
Solution:
dean