Utopianism isn’t really a movement, though there are of course movements that are Utopian. Utopian is a specialized definition. Conquest of Bread is the most classic kind of Utopian literature, trying to puzzle out a way of building society from the ground up to not have the social ills and poverty Kropotkin saw in his time. Not all anarchists are Utopians (not all of them concern themselves specifically with the positive machinations of the proposed final circumstances), but Kropotkin definitely was.