Short answers, pulled from the story.
Alexander Blok was the most well-known Russian lyrical poet of the Silver Age of Russian Poetry, active from the late 19th century until his death on the 7th of August 1921. He was a central figure in Russian Symbolism and was compared to Alexander Pushkin. Anna Akhmatova, Marina Tsvetaeva, Boris Pasternak, and Vladimir Nabokov all wrote verse tributes to him.
The Twelve, written in 1918, describes twelve Red Guards marching through the streets of revolutionary Petrograd during the Russian Civil War, with a fierce winter blizzard raging around them. Blok likened the soldiers to the Twelve Apostles of Christ and placed Jesus Christ walking ahead of them. The Encyclopaedia Britannica described the poem's "mood-creating sounds, polyphonic rhythms, and harsh, slangy language."
Blok married Lyubov Dmitrievna Mendeleeva, an actress and daughter of the chemist Dmitri Mendeleev, in 1903. He dedicated his most celebrated early poetry cycle, Stikhi o Prekrasnoi Dame (Verses About the Beautiful Lady, 1904), to her. Their marriage also drew Blok into a complicated love-hate relationship with the Symbolist poet Andrei Bely.
Blok died on the 7th of August 1921 from asthma and scurvy. His doctors had requested he be sent abroad for medical treatment, but Soviet authorities initially refused. Maksim Gorky pleaded for a visa, and a resolution permitting Blok's departure was signed by the Political Bureau on the 23rd of July 1921, but the final permission was not delivered until the 10th of August, three days after his death.
In 1923, Leon Trotsky devoted a whole chapter of his book Literature and Revolution to Blok. Trotsky wrote that "Blok belonged to pre-October literature, but he overcame this, and entered into the sphere of October when he wrote The Twelve. That is why he will occupy a special place in the history of Russian literature."
Dmitri Shostakovich wrote Seven Romances on Poems by Alexander Blok, Op. 127 for soprano and piano trio. Mieczyslaw Weinberg composed Beyond the Border of Past Days, Op. 50, and Georgy Sviridov set Blok's verse in works including a vocal poem titled Petersburg, a cantata called Nightly Clouds, and a concerto called Songs From Hard Times. Arthur Lourie wrote a choral cantata called In the Sanctuary of Golden Dreams.