If assurances were given that the president of the united states would not participate in an attack on cuba and the blockade lifted, then the question of the removal or the destruction of the missile sites in cuba would then be an entirely different question."

The letter came from Khrushchev and the letter was for Kennedy which he received on October 26. This happened during the Cuban Missile Crisis.

Leaders of the Soviet Union and United States were occupied rigid 13-day military and political standoff in October 1962 regarding the installation of nuclear-armed Soviet missiles on Cuba which was just 90 miles away from the shores of the United States.

answer:

it caused mass african migration, african populations to grow, african empires to topple, and racism against slaves to emerge.