Utopias are perfectly organized societies that provide for all the wants and needs of individuals. As such they rarely exist in practice for any length of time and are usually presented in various forms of literature with highly prescriptive rules and regulations. In other words, utopias tend to be offered as hierarchical and even authoritarian constructs. The idea is that rules and regulations if properly applied can generate the hoped-for results.
Utopianism is a variant of the utopian scheme in that utopianism often points to previous eras that are held up as a more perfect expression of human society. This is doubtless a false perception (or may be one at least) but no one is in a position to disprove it.
What are some utopian eras? The Garden of Eden is one of the most obvious ones from a Western perspective. Atlantis might be said to be another. A third might be the Greek Golden Age. But most utopian visions exist in books rather than in history. Wikipedia provides a list:
• The Republic (written around 380 BCE) by Plato is one of the earliest conceptions of a utopia.
• The City of God (written 413–426 AD) by Augustine of Hippo, describes an ideal city, the "eternal" Jerusalem, the archetype of all Christian utopias.
• Tao Hua Yuan, (421 AD) is a utopia for Chinese intellects.
• Al-Madina al-Fadila, written by Al-Farabi (874-950 AD), where he theorized an ideal state as in Plato's The Republic.
• Utopia (1516) by Thomas More.
• Christianopolis (1619) by Johann Valentin Andreæ, describes a Christian utopia inhabited by a community of scholar-artisans and run as a democracy.
• The City of the Sun (1623) by Tommaso Campanella depicts a theocratic and egalitarian society.
• New Atlantis (1627) by Francis Bacon.
• Erewhon (1872) by Samuel Butler, constitute a satiric romp through a hidden utopia (with dystopian elements) in the mountains of New Zealand.
• News from Nowhere by William Morris (1892), Shows "Nowhere", a place without politics, a future society based on common ownership and democratic control of the means of production.
• Looking Backward (1888) by Edward Bellamy.
• Gloriana, or the Revolution of 1900 (1890) by Lady Florence Dixie. The female protagonist poses as a man, Hector l'Estrange, is elected to the House of Commons, and wins women the vote. The book ends in the year 1999, with a description of a prosperous and peaceful Britain governed by women.
Conspiratorial historians in the era of the Internet have increasingly come to the conclusion that an intergenerational, familial banking elite has sponsored many of humankind's utopian schemes, at least in the West in the modern era. There is considerable evidence that in the 20th century anyway Western banks and financial centers funded the Russian Revolution, Hitler's fascist takeover of Germany and even Maoist Marxism.
This is because utopian schemes are inevitably attractive and authoritarian at the same time. They are relatively easy to create while promising in their evolution to provide maximum chaos to domestic and international society. The elites behind these utopias do not seek the realization of utopian promises but, rather, their chaotic devolution. Out of such chaos, Anglo-American elites (mostly) seek opportunities to accrue further profit and power. There is no such thing as a utopia but this does not stop elites from participating first in their erecting and then in their wrecking.