Languages and Writing
People spoke two major language groups in the Mediterranean and West Asian areas in the ancient and medieval periods. These are Indo-European and Semitic. In southern Africa, most people spoke either a Bantu language or a Khoisan language. Indo-European languages came to be spoken in India as well, but other languages also were spoken. In Central Asia, most people spoke variations of Turkic languages. And in China, people spoke different variants of Chinese.
The Indo-European language group seems to have originated between the Black Sea and the Caspian Sea, in modern Georgia (see map). Around 3000 BC some of the people who spoke this language began to travel away from here. Some of them went west toward the Atlantic ocean and these are now known as the Celts, and they speak the Celtic languages: Gaelic, Welsh, Breton and Cornish. Another group went east toward China, and these are now known as the Tocharians, though they speak Chinese now. A little later, others travelled over the Black Sea toward the Mediterranean or south to West Asia. Some of them settled in Italy, where Indo-European became Latin. Others settled in Greece, where Indo-European became Greek. Some went to West Asia, where they spoke Hittite and Persian, and some went all the way south to India, where they spoke Sanskrit. Some went north, where Indo-European turned into German, Danish, Swedish, and English. The people who stayed more or less where they were in the Balkans and Russia began to speak the Slavic and Baltic languages: Russian, Polish, Lithuanian.
The Semitic languages include Hebrew, Arabic, Aramaic (the language of Jesus and his disciples), Canaanite, Akkadian, Phoenician, Syriac, and, as more distant relations, ancient Egyptian, modern Berber, and some of the languages of East Africa. They were spoken mainly in West Asia, along the coast of the Mediterranean Sea, in the Arabian peninsula, and along the Mediterranean and East coasts of Africa. Most likely the language group started out somewhere around Lebanon or Syria, and spread from there eastward into Mesopotamia and southward into the Arabian peninsula and Egypt (see map). Egyptian split off very early, and is very different from the other Semitic languages. Arabic seems to be the closest to what Semitic languages were like a long time ago, probably because people who spoke Arabic lived in the Arabian peninsula and rarely met people who spoke other languages. So their language didn't change much, while the Jews, Phoenicians, and others who lived along the Mediterranean coast were always talking to strangers, and this changed their language more quickly. When the Umayyads conquered North Africa and West Asia in the 600s AD, they brought Arabic with them to most of the Islamic Empire, though people kept on speaking the old Indo-European languages, Persian or Kurdish, in Iran. Then not long afterward, Central Asian speakers of Turkic languages moved into West Asia, and people in Turkey learned to speak Turkish instead of Arabic.
Learn by doing: learn some words in another language
More about the Indo-Europeans
In Search of the Indo-Europeans: Language, Archaeology, and Myth by J. P. Mallory.
Empires of the Word : A Language History of the World, by Nicholas Ostler (2005).