Western culture was influenced by many older great civilizations of the ancient Near East, such as Phoenicia, Ancient Israel, Minoan Crete, Sumer, Babylonia, and also Ancient Egypt. It originated in the Mediterranean basin and its vicinity; Ancient Greece and Rome are often cited as its birthplaces.
Over time, their associated empires grew first to the east and west to include the rest of Mediterranean and Black Sea coastal areas, conquering and absorbing. Later, they expanded to the north of the Mediterranean Sea to include Western, Central, and Southeastern Europe. Christianization of Ireland (5th century), Christianization of Bulgaria (9th century), Christianization of Kievan Rus' (Russia, Ukraine, Belarus; 10th century), Christianization of Scandinavia (Denmark, Norway, Sweden; 12th century) and Christianization of Lithuania (14th century) brought the rest of present-day European territory into Western civilization.
Historians, such as Carroll Quigley in "The Evolution of Civilizations", contend that Western civilization was born around AD 500, after the total collapse of the Western Roman Empire, leaving a vacuum for new ideas to flourish that were impossible in Classical societies. In either view, between the fall of the Western Roman Empire and the Renaissance, the West (or those regions that would later become the heartland of the culturally "western sphere") experienced a period of first, considerable decline, and then readaptation, reorientation and considerable renewed material, technological and political development. This whole period of roughly a millennium is known as the Middle Ages, its early part forming the "Dark Ages", designations that were created during the Renaissance and reflect the perspective on history, and the self-image, of the latter period.
The knowledge of the ancient Western world was partly preserved during this period due to the survival of the Eastern Roman Empire and the introduction of the Catholic Church; it was also greatly expanded by the Arab importation of both the Ancient Greco-Roman and new technology through the Arabs from India and China to Europe.
Since the Renaissance, the West evolved beyond the influence of the ancient Greeks and Romans and the Islamic world, due to the successful Second Agricultural, Commercial, Scientific, and Industrial revolutions (propellers of modern banking concepts) peaked with the 18th century's Age of enlightenment, through the Age of exploration's expansion of peoples of Western and Central European empires, particularly the globe-spanning colonial empires of 18th and 19th centuries. Numerous times, this expansion was accompanied by Catholic missionaries, who attempted to proselytize Christianity.
Generally speaking, the current consensus would locate the West, at the very least, in the cultures and peoples of Europe (at least the European Union member states, EFTA countries, European microstates), the United States, Canada, Australia, New Zealand, and parts of Latin America. There is debate among some as to whether Latin America as a whole is in a category of its own. Whether Russia should be categorized as "East" or "West" has been "an ongoing discussion" for centuries.