Passed can mean move or cause something to move in a specific way or it can mean go past or across something.
Past can mean gone by in time and no longer existing or happening.
Most European countries were in expansion of conquest, and Africa was a found ground for it. Many Africans were kidnapped from Western Africa and brought to Portugal. But a reason can be for the economic prosperity the slave trade brought to those countries.
They contributed to the decline of feudalism.
