Anna Akhmatova, the Grand Dame of the Russian poetry and the belle of the Russian silver age, did not enter earlier because she belongs with Boris Pasternak to the neo-classicist wing of the poetic endeavor. Yet, she was a pupil and wife of Gumilev, a friend of Mandelstams and a mentor to Brodsky. She also was a lover of Modigliani and Isaiah Berlin. If this were not enough, her Requiem was not only a masterpiece of Russian XX century poetry, easily comparable to J. Alfred Prufrock or the Waste Land, but also a watershed between the poetry of the first half of the XX century centered on St. Petersburg and its second half centered on Moscow.
Requiem written in the memory of the victims of Stalinist terror--among whom were her third (common law) husband, art historian, Punin (died in the camps after the death of Stalin) and her son Lev Gumilev (spent 15 years in Gulag)--is not only a monument to her civic consciousness but also the great work of art. Read it.
P. S. Anna Akhmatova Requiem is one of the most translated Russian poems in English and I defer to the earlier translators. One of rather faithful translations is provided by Evgeny Bovner.
P.S. Akhmatova and her comedienne friend Faina Ranevskaya in their later years were accomplished conversationalist broads pronouncing brush, harsh and hilarious judgments on the contemporary literary and political scene.