The first major distinction is between prehistory and history. Basically, history is the timeframe for which we can (attempt to) date events with reasonably good precision and we know the names of at least some important people, usually rulers. Everything earlier is prehistory. By and large, history begins in the 3rd millenium before the common era, in Mesopotamia and Egypt, with the oldest written documents that we can read.
There is no such thing as a universal periodization of history; we the participants to this forum are more familiar with the periodization pertaining to the lineage of civilizations which eventually resulted in the modern western civilization (Europe, the Americas, Australia, parts of Asia, parts of Africa). This is commonly organized as follows:
- Preclassical, or deep antiquity: from the earliest document to about the 6th century before the common era.
Major event: the Battle of Marathon, 490 BCE. The western world separates decisively from the Near East / Middle East.
- Classical period: from the 6th century before the common era to the 3rd or 4th century of the common era. This is the age of the Greek, Hellenistic and Roman civilizations; it lasted for about one thousand years.
Major event: the fall of the Western Roman Empire, 476 CE. Western Europe is broken into a multitude of small and weak centers of power.
- Post-classical antiquity: a brief period between the classical world and the Middle Ages; roughly from the 3rd or 4th century to the 6th century of the common era. In this time the classical world mostly disintegrated and the feudal relationships specific to the Middle Ages were established. The major powers in our lineage were the (Eastern) Roman (aka Byzantine) Empire and the Persian Empire.
Major events: the (Eastern) Roman (aka Byzantine) Empire loses Syria and Egypt to the Arabs. The classical world dies forever.
The Middle Ages, from roughly the 6th or 7th to the 14th or 15th century; about 8 or 9 centuries. It covers the time span between the fall of the classical world and the rapid developments of the Renaissance.
The essential characteristics of the Middle Ages are feudalism and the existence of numerous small centers of power, which were only very loosely structured in larger kingdoms or empires. Another important characteristic of the Middle Ages is that the loyalties of people were to persons and not to countries or institutions; this makes the medieval world very different from the classical antiquity and the modern world; please note that in a story set in the Middle Ages it makes no sense to have patriots (there is no concept of loyalty to a nation, and there is no concept of a nation as a political structure).
Major events: fall of Constantinople to the Ottomans (1453), Columbus reaches the New World (1492), Vasco da Gama reaches India (1498).
- The Renaissance, a short period from the 14th to the early 17th century; this is a time of rapid developments in culture, science and technology, and of geographical discoveries. This unprecedented developments resulted in the dissolution of the feudal bonds and the emergence of the modern world. The Renaissance begans asynchronously in different parts of Europe; by the late 14th century Italy was in full Renaissance mood, whereas northern regions such as England and the Germanies were still fully medieval.
Major event: the 30 Years War, 1618-1648. Almost western and central European states are involved.
The Modern age, usually reckoned to begin with the Peace of Westphalia which ended the 30 Years War. (Sometimes the Renaissance is subsumed as the first part of the Modern age, or as the last part of the Middle Ages.) The major characteristic of this ages is the emergence of sovereign states as the principal actors on the historical stage, and the universal importance of the rule of law. It is usually divided into:
- The Early Modern period, which saw the first industrial revolution, and
- The Late Modern period or the age of machines, beginning with the second industrial revolution in the 19th century.
This periodization is made simply in order to make it easier for students to understand historical development. The people actually living in the 6th century did not in any way have a feeling that they were living in a time of transition between the Antiquity and the Middle Ages. The guiding principle of the periodization of history is finding great commonalities, in social structure, culture, economy and so on.
It is important to understand that any periodization of history is specific to a civilization or to a lineage of civilizations; for example, the division between the Renaissance and the Modern age is highly specific to the European civilization and it is completely meaningless to the Oriental civilizations of India, China, Indochina and Japan. For and Indian, or a Chinese, or a Japanese history has different periods specific to the development of their civilizations; for example, in the history of Japan the modern period begins with the Meiji Restoration in the second half of the 19th century.