In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Let me give you an example: 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.
The answer to this example can be: Russian Revolution
Here is why: This is a good example, and the Russian Revolution is the first event mentioned.

OK. solve this:
When did the popularity of the Athenian serenades begin?, Context: The Heptanesean kantádhes (καντάδες 'serenades'; sing.: καντάδα) became the forerunners of the Greek modern song, influencing its development to a considerable degree. For the first part of the next century, several Greek composers continued to borrow elements from the Heptanesean style. The most successful songs during the period 1870–1930 were the so-called Athenian serenades, and the songs performed on stage (επιθεωρησιακά τραγούδια 'theatrical revue songs') in revue, operettas and nocturnes that were dominating Athens' theater scene.
Answer:
1870