Plato, Republic. In a sense, the utopian genre might be said to begin with Plato’s Republic, in which he sets out his ideal society (famously, no poets were allowed). The Republic sees Socrates debating with a number of other people about the nature of justice and the ideal city-state. The book also discusses various possible forms of government, discussing the advantages and disadvantages of each.
Francis Bacon's New Atlantis was probably written in 1624, but was not published until 1627, a year after the author's death. Like the work of his contemporaries, Campanella and Andreae, Bacon's book shows the influence of More in certain broad aspects. It purports to relate the discovery by an exploring expedition in the Pacific Ocean of an island where the natives have developed a society offering much to admire. The goal of the common good is sought through learning and justice. The principal attention of the account is focused on an elaborate academy of science. Bacon has incorporated in this society the basic ideas that he developed more elaborately in his longer philosophical and scholarly treatises; namely, that the advancement of human welfare can best be achieved through the systematic exploration of nature. His famous "scientific method" is founded on painstaking observation of natural phenomena and constructing, through inductive reasoning, a body of knowledge based on those observations. He urges experimentation to improve general knowledge and to develop inventions for human comfort and pleasure. The central institute in the capital of New Atlantis, called Solomon's House, is a huge academy which foreshadows the later creation of scientific laboratories and academies, such as the English Royal Society.
There is, of course, nothing new in all of this program, nothing fantastic such as Huxley's "Hatchery and Conditioning Centre." The reader, while he cringes at the horror, keeps repeating to himself, "It can't happen here." Nevertheless, Orwell compels us to recognize not only Nazi devices but also certain telltale symptoms in our own social and political practices that cannot help but undermine our complacency. 

Italy was unquestionably the fountainhead of Renaissance civilization. As early as the 14th century, men of enlightenment, notably Petrarch and Boccaccio, were introducing Renaissance concepts and proclaiming a new allegiance to classical antiquity, and through the 15th century a feverish development toward new attitudes and styles marked the work of brilliant artists, scholars, philosophers, and men of letters. Through most of the 15th century, the achievements were predominantly Italian, but by the beginning of the 16th century the movement was spreading to other countries of western Europe; at the same time that Italy was losing her political independence through conquests by French, Spanish, and Austrian armies, she gradually yielded her preeminence in the arts and letters to France, Spain, and England.
Cicero's De republica (54–52 B.C.) is largely indebted to Plato, not only to the Republic but also to several other Platonic dialogues. Cicero discusses the attributes of various types of government — monarchy, aristocracy, democracy, and dictatorship — but without committing himself to a preference. One point, however, is clear. His concept of an ideal state is one based on reason and justice, where those who possess natural superiority rule over the inferiors.
Denis Diderot's Supplement to Bougainville's "Voyage" (1772) is a prime example of the eighteenth-century vogue of primitivism which was spurred by Rousseau's thesis of the "noble savage" and which generated such novels as St. Pierre's Paul and Virginia and Chateaubriand's Atala. Diderot's book makes a case for the simple, natural ways of a South Sea Island culture as reported by Bougainville, a French explorer. The central portion of the story presents an imaginary dialogue between a French chaplain and a native of Tahiti (Orou) in which a comparison is made between the customs and institutions of Europe and those of Tahiti. The way of life of the islanders is eloquently defended, and that of the Europeans discredited. According to the Tahitian, man's natural instincts, which are equated with the laws of nature, are interpreted as justifying complete freedom in sexual relations. Their observance of community property is defended as minimizing personal conflicts and legal entanglements and promoting a general concern for the welfare of the community as a whole.