The Western world, also known as the West, primarily refers to various nations and states in Western Europe, Northern America, and Australasia; with some debate as to whether those in Eastern Europe and Latin America also constitute the West. The Western world likewise is called the Occident (from Latin occidens 'setting down, sunset, west') in contrast to the Eastern world known as the Orient (from Latin oriens 'origin, sunrise, east'). Definitions of the "Western world" vary according to context and perspectives; the West is an evolving concept made up of cultural, political, and economic synergy among diverse groups of people, and not a rigid region with fixed borders and members.
Some historians contend that a linear development of the West can be traced from Ancient Greece and Rome, while others argue that such a projection constructs a false genealogy. A geographical concept of the West started to take shape in the 4th century CE when Constantine, the first Christian Roman emperor, divided the Roman Empire between the Greek East and Latin West. The East Roman Empire, later called the Byzantine Empire, continued for a millennium, while the West Roman Empire lasted for only about a century and a half. Significant theological and ecclesiastical differences led Western Europeans to consider the Christians in the Byzantine Empire as heretics. In 1054 CE, when the church in Rome excommunicated the patriarch of Byzantium, the politico-religious division between the Western church and Eastern church culminated in the Great Schism or the East–West Schism. Even though friendly relations continued between the two parts of Christendom for some time, the crusades made the schism definitive with hostility. The West during these crusades tried to capture trade routes to the East and failed, it instead discovered the Americas. In the aftermath of the European colonization of the Americas, primarily involving Western European powers, an idea of the "Western" world, as an inheritor of Latin Christendom emerged. According to the Oxford English Dictionary, the earliest reference to the term "Western world" was from 1586, found in the writings of William Warner.
