The wealth of the Mawarannahr region is a constant magnet for invasions from the northern steppes and from China.

Numerous intraregional wars are fought between Sogdian states and the other states in Mawarannahr, and the Persians and the Chinese are in perpetual conflict over the region.

Alexander the Great conquers the region in 328 BCE, bringing it briefly under the control of his Macedonian Empire.

In the same centuries, however, the region also is an important center of intellectual life and religion.

Alexander's empire is divided among his Macedonian generals after his death.

The eastern part—Phoenicia, Asia Minor, northern Syria, and Mesopotamia—fall to Seleucus I, founder of the Seleucid dynasty.

The southern part of Syria and Egypt fall to Ptolemy, and the European part, including Macedon, to Antigonus I.

This settlement, however, fails to bring peace because Seleucus I and Ptolemy clash repeatedly in the course of their ambitious efforts to share in Phoenician prosperity.

A final victory of the Seleucids ends a forty-year period of conflict.

Nearly all of Babylon opposed the Achaemenids by the fourth century BCE.

Thus, when the Iranian forces stationed in Babylon surrender to Alexander the Great of Macedon in 331 BCE, all of Babylonia hails him as a liberator.

Alexander quickly wins Babylonian favor when, unlike the Achaemenids, he displays respect for such Babylonian traditions as the worship of their chief god, Marduk.

Alexander also proposes ambitious schemes for Babylon.

He plans to establish one of the two seats of his empire here and to make the Euphrates navigable all the way to the Persian Gulf, where he plans to build a great port.

Alexander's grandiose plans, however, never come to fruition.

Returning from an expedition to the Indus River, he dies in Babylon—most probably from malaria contracted there in 323 BCE—at the age of thirty-two.

His generals fight for and divide up his empire in the politically chaotic period after Alexander's death.

Many of the battles among the Greek generals are fought on Babylonian soil.

Greek military campaigns in the latter half of the Greek period are focused on conquering Phoenician ports and Babylonia is thus removed from the sphere of action.

The city of Babylon loses its preeminence as the center of the civilized world when political and economic activity shift to the Mediterranean, where it  is destined to remain for many centuries.

The effects of the Greek occupation are noteworthy, even though Alexander's major plans for Mesopotamia go unfulfilled, and his generals do little that is positive for Mesopotamia.

Alexander and his successors build scores of cities in the Middle East that are modeled on the Greek city-states.

One of the most important is Seleucia on the Tigris.

The Hellenization of the area includes the introduction of Western deities, Western art forms, and Western thought.

Business revives in Mesopotamia because one of the Greek trade routes runs through the new cities.

Mesopotamia exports barley, wheat, dates, wool, and bitumen; the city of Seleucia exports spices, gold, precious stones, and ivory.

Cultural interchange between Greek and Mesopotamian scholars is responsible for the saving of many Mesopotamian scientific, especially astronomical, texts.

Local political power in Greater Syria—which probably would have continued to contest for control of the region—is effectively shattered when Alexander the Great conquers the Persian Empire in 333, and the area comes into the strong cultural orbit of Western ideas and institutions.

Alexander's empire is divided at his death among five of his generals.

General Seleucus becomes heir to the lands formerly under Persian control, which includes Greater Syria.

The Seleucids will rule for three centuries and found a kingdom later referred to as the Kingdom of Syria.

Seleucus names many cities after his mother, Laodicea; the greatest becomes Latakia, a major Syrian port.

The Persian Empire eventually falls to Alexander the Great, king of Macedonia.

He attacks Asia Minor, defeats the Persian troops in 333 BCE, and advances toward the Lebanese coast.

Initially the Phoenician cities make no attempt to resist, and they recognize his suzerainty.

Tyre resists, however, when Alexander tries to offer a sacrifice to Melkurt, the city's god.

Alexander besieges Tyre in retaliation in early 332 BCE.

The city falls after six months of resistance, and its people are sold into slavery.

Alexander's conquest of the eastern Mediterranean Basin leaves a Greek imprint on the area despite his early death in 323 BCE.

The Phoenicians, being a cosmopolitan people amenable to outside influences, adopt aspects of Greek civilization with ease.

Enormous numbers of Greek immigrants flock to the Kingdom of Syria.

Syrian trade is vastly expanded as a result of the newcomers' efforts, reaching into India, the Far East, and Europe.

The Greeks build new cities in Syria and colonize existing ones.

Syrian and Greek cultures synthesize to create Near Eastern Hellenism, noted for remarkable developments in jurisprudence, philosophy, and science.

A series of other conquests of varying lengths follows in the Persian Gulf region.

Alexander the Great sends a fleet from India in 325 BCE to follow the eastern, or Persian, coast of the gulf up to the mouth of the Tigris and Euphrates rivers and sends other ships to explore the Arab side of the waterway.

The temporary Greek presence in the area increases Western interest in the gulf during the next two centuries.

Alexander's successors, however, do not control the area long enough to make the gulf a part of the Greek world.

The Greeks lose all territory east of Syria to the Parthians, a Persian dynasty in the East,
by about 250 BCE.

The Parthians bring the gulf under Persian control and extend their influence as far as Oman.

The Parthian conquests demarcate  the distinction between the Greek world of the Mediterranean Sea and the Persian Empire in the East.

The Greeks, and the Romans after them, depend on the Red Sea route, whereas the Parthians depend on the Persian Gulf route.

The Parthians, because they want to keep the merchants who ply these routes under their control, establish garrisons as far south as Oman.

The Persian Empire falls to Alexander the Great in 330 BCE, and he continues his march eastward through Afghanistan and into India.

Alexander defeats Porus, the Gandharan ruler of Taxila, in 326 BCE and marches on to the Ravi River before turning back.

The return march through Sindh and Balochistan ends with Alexander's death at Babylon in 323 BCE.

Greek rule does not survive in northwestern India, although a school of art known as Indo-Greek develops and influences art as far as Central Asia.

The region of Gandhara is conquered by Chandragupta (r. ca. 321-ca. 297 BCE), the founder of the Mauryan Empire, the first universal state of northern India, with its capital at present-day Patna in Bihar.

His grandson, Ashoka (r. ca. 274-ca. 236 BCE), becomes a Buddhist.

Taxila becomes a leading center of Buddhist learning.

Successors to Alexander at times control the northwestern region of present-day Pakistan and even the Punjab after Mauryan power wanes in the region.