What is a union of independent sovereign states?

A union of independent sovereign states is a confederation. This is also used to refer to an organization that consists of a number of parties or groups united in an alliance or league. Hope this answers the question.

currancy

explanation:

its main object was the establishment of "settlement houses" in poor urban areas, in which volunteer middle-class "settlement workers" would live, hoping to share knowledge and culture with, and alleviate the poverty of, their low-income neighbors.