By the mid seventeenth century there were six European countries that established colonies that were mostly or partially on the Atlantic coast. This includes colonies on three continents, North America, South America, and Africa. The six countries are:
British Empire; Mainly focused on the North American continent.
France; Focused on the western coast of Africa and part of North America.
Spain; Focused on the Central part of America and part of the eastern coast of South America.
Portugal; Focused on the eastern coast of South America.
Belgium; It had Congo under its rule and a very little part of the western coast of Africa.
The Netherlands; Focused on the Caribbean Islands and little part of the eastern coast of South America.