| Asia is the largest and most populous | | | | American English, Asian refers to East |
| region or continent depending on the | | | | Asian (Orientals), while in British |
| definition. It is traditionally defined | | | | English, Asian refers to South Asian |
| as part of the landmass of | | | | reflects this confusion. Sometimes, it |
| Africa-Eurasia – with the western | | | | is not even clear exactly what "Asia" |
| portion of the latter occupied by Europe | | | | consists of. |
| – lying east of the Suez Canal, east | | | | Some definitions exclude Turkey, the |
| of the Ural Mountains, and south of the | | | | Middle East, or Russia. The term is |
| Caucasus Mountains and the Caspian and | | | | sometimes used more strictly in |
| Black Seas. About 60% of the world's | | | | reference to Asia Pacific, which does |
| human population lives in Asia. | | | | not include the Middle East or Russia, |
| Medieval Europeans considered Asia as a | | | | but does include islands in the Pacific |
| continent, a distinct landmass. The | | | | Ocean — a number of which may also be |
| European concept of the three continents | | | | considered part of Australasia or |
| in the Old World goes back to classical | | | | Oceania. Asia contains the Indian |
| antiquity with the etymology of the word | | | | subcontinent, Arabian subcontinent, as |
| rooted in the ancient Near and Middle | | | | well as a piece of the North American |
| East. The demarcation between Asia and | | | | plate in Siberia. |
| Africa is the Isthmus of Suez and the | | | | The history of Asia can be seen as the |
| Red Sea. The boundary between Asia and | | | | distinct histories of several peripheral |
| Europe is commonly believed to run | | | | coastal regions East Asia, South Asia, |
| through the Dardanelles, the Sea of | | | | and the Middle East ; linked by the |
| Marmara, the Bosporus, the Black Sea, | | | | interior mass of the Central |
| the Caucasus Mountains, the Caspian Sea, | | | | Asiansteppes. |
| the Ural River to its source, and the | | | | The coastal periphery was home to some |
| Ural Mountains to the Kara Sea near | | | | of the world's earliest known |
| Kara, Russia. However, modern discovery | | | | civilizations, each of them developing |
| of the extent of Africa and Asia made | | | | around fertile river valleys. The |
| this definition rather anachronistic, | | | | civilizations in Mesopotamia, the Indus |
| especially in the case of Asia, which | | | | Valley, and the Yangtze shared many |
| would have several regions that would be | | | | similarities, and may well have |
| considered distinct landmasses if these | | | | exchanged technologies and ideas such as |
| criteria were used (for example, South | | | | mathematics and the wheel. Other |
| Asia and East Asia). | | | | innovations, such as that of writing, |
| Geologists and physical geographers no | | | | seem to have been developed individually |
| longer consider Asia and Europe to be | | | | in each area. Cities, states and empires |
| separate continents. It is either | | | | developed in these lowlands. |
| defined in terms of geological | | | | The central steppe region had long been |
| landmasses (physical geography) or | | | | inhabited by horse-mounted nomads, and |
| tectonic plates (geology). In the former | | | | from the steppes they could reach all |
| case, Europe is a western peninsula of | | | | areas of Asia. The earliest postulated |
| Eurasia or the Africa-Eurasia landmass. | | | | expansion out of the steppe is that of |
| In the latter, Europe and Asia are parts | | | | the Indo-Europeans, who spread their |
| of the Eurasian plate, which excludes | | | | languages into the Middle East, India, |
| the Arabian and Indian tectonic plates. | | | | and in the Tocharians, to the borders of |
| In human geography, there are two | | | | China. The northernmost part of Asia, |
| schools of thought. One school follows | | | | including much of Siberia, was largely |
| historical convention and treats Europe | | | | inaccessible to the steppe nomads, owing |
| and Asia as different continents, | | | | to the dense forests, the climate, and |
| categorizing Europe, East Asia (the | | | | the tundra. These areas remained very |
| Orient), South Asia (British India), and | | | | sparsely populated. |
| the Middle East (Arabia and Persia) as | | | | The center and the peripheries were |
| specific regions for more detailed | | | | mostly kept separated by mountains and |
| analysis. The other schools equate the | | | | deserts. The Caucasus and Himalaya |
| word "continent" in terms of | | | | mountains and the Karakum and Gobi |
| geographical region when referring to | | | | deserts formed barriers that the steppe |
| Europe, and use the term "region" to | | | | horsemen could cross only with |
| describe Asia in terms of physical | | | | difficulty. While technologically and |
| geography. Because in linguistic terms, | | | | socially, the urban city dwellers were |
| "continent" implies a distinct landmass, | | | | more advanced, in many cases they could |
| it is becoming increasingly common to | | | | do little in a military aspect to defend |
| substitute the term "region" for | | | | against the mounted hordes of the |
| "continent" to avoid the problem of | | | | steppe. |
| disambiguation altogether. | | | | However, the lowlands did not have |
| There is much confusion in European | | | | enough open grasslands to support a |
| languages with the term "Asian". Because | | | | large horsebound force; for this and |
| a category implies homogenity, the term | | | | other reasons, the nomads who conquered |
| "Asian" almost always refers to a | | | | states in China, India, and the Middle |
| subcategory of people from Asia rather | | | | East often found themselves adapting to |
| than referring to "Asian" defined in | | | | the local, more affluent societies. |
| term of "Asia". The fact that in | | | | |