What event triggered the intercontinental population movement along the Atlantic coast?

A new route has been opened. With the opening of a new air route, the intercontinental population movement along the Atlantic coast began. According to the knowledge learned, after the opening of the new air route, European countries embarked on the road of colonial plunder and colonial expansion. As can be seen from the pictures in the materials, from Europe to America, it belongs to voluntary immigration, and from Africa to America, it belongs to compulsory immigration.