Short answers, pulled from the story.
Nikita Khrushchev was born on the 15th of April 1894 in Kalinovka, a village in what is now the Khomutovsky District of Kursk Oblast in western Russia, near the present Ukrainian border. His parents were poor Russian peasants.
Khrushchev delivered the Secret Speech on the 25th of February 1956 to a closed session of the 20th Party Congress. In four hours, he denounced Stalin's purges, brutality, and abuse of power, launching the era of de-Stalinization. Despite being delivered in secret, copies were circulating across the Soviet Union by the 5th of March and reached the West within weeks.
After Stalin died on the 5th of March 1953, Khrushchev outmaneuvered his rivals, starting with helping to arrest and execute Lavrentiy Beria on the 26th of June 1953. He then used his control of the Party's Central Committee to sideline Malenkov, who was demoted in January 1955. Khrushchev consolidated power fully in March 1958 when he took the premiership from Bulganin.
Khrushchev actively supported the Great Purge. In June 1937, after the Politburo set a quota of 35,000 enemies to be arrested in Moscow province, Khrushchev asked that 2,000 kulaks be killed in partial fulfillment. Two weeks later he reported that 41,305 people had been arrested. Of the 38 top Party officials in Moscow city and province, 35 were killed while Khrushchev held that post.
Khrushchev was removed from the Soviet leadership on the 14th of October 1964 after his rivals consolidated enough support among the nomenklatura to oust him. His domestic policy failures, particularly in agriculture, and his handling of the 1962 Cuban Missile Crisis had significantly weakened his position in the early 1960s.
After his forced retirement, Khrushchev spent much of his time at his dacha composing lengthy memoirs, which were smuggled to the West and published in part in 1970. He died on the 11th of September 1971.