Mussorgsky's 'Boris Gudonov' Performed is a 
Russian event regarding the premiere of Mussorgsky's opera Boris Godunov.
It can happen anytime between 1874 and 1877 with no other requirements. It has a mean time to happen of 5 months, which will decrease by 25% after 1875 and another 5% after 1876.
It gives Russia 5 prestige and all Russian POPs 1 consciousness.
Ingame Decription
On 8 February 1874, after years of work and revisions, Mussorgsky's opera 'Boris Gudonov' was published and it's inaugaral performance. Seeking to blend Russian Folk Music with the ideas Richard Wagner, the Opera aimed to present itself as a truly national work of music.