Alexander the Great was king of the Macedonians and one of the greatest generals in history. He conquered the Persian Empire, which stretched from the Mediterranean Sea to India and formed much of what was then considered the civilized world. Alexander's conquests furthered the spread of Greek ideas and customs in western Asia and Egypt. He thus made possible the rich culture of the Hellenistic Age.

Alexander was born in Pella, the capital of the Macedonian kingdom. His father was Philip II, the shrewd king and general who conquered Greece. His mother was Olympias, a brilliant and hot-tempered princess from Epirus in western Greece. Olympias told Alexander that his ancestor was the hero Achilles. Throughout his life, Alexander carried with him a copy of the great poem the Iliad, which told of the deeds of Achilles. Philip taught Alexander that the Macedonian kings were descended from the hero Hercules (also called Heracles), who in Greek mythology was a son of the god Zeus.

There are many stories about Alexander's life. Some are true, but others are legends. According to one story, the boy Alexander tamed the great horse Bucephalus. This magnificent steed later carried Alexander as far as India, where it died. Alexander built a city there and named it Bucephala after the horse.

In 343 or 342 B.C., Philip hired the great philosopher Aristotle to tutor Alexander. Aristotle may have encouraged Alexander's interest in other countries and peoples, as well as his curiosity about plants and animals.

Alexander's education followed the Greek principle of "a sound mind in a sound body." He studied literature, philosophy, and politics, and he also received training in sports, physical fitness, and warfare. Alexander's official schooling ended abruptly at the age of 16, when his father called him away for duties in the government.

In 338 B.C., the 18-year-old Alexander commanded the cavalry in Philip's army in the Battle of Chaeronea. This battle brought Greece under Macedonian control. Philip next prepared to invade the Persian Empire in Asia. But before he could do so, Philip was murdered by one of his bodyguards. Thus, at the age of 20, Alexander became king of the Macedonians.

After Philip's death, some Greek cities under Macedonian rule revolted. In 335 B.C., Alexander's army stormed the walls of the rebellious city of Thebes and demolished the city. About 30,000 inhabitants of the city were sold into slavery. Alexander's action against Thebes discouraged, for a time, rebellion by other Greek cities.

With Greece under control, Alexander turned to his father's plan for attacking the Persian Empire. In 334 B.C., he led an army of about 35,000 infantry and cavalry across the Hellespont from Europe to Asia. The Persians sent out troops that met Alexander's forces at the Granicus River. Alexander and his cavalry charged across the river and won the battle. This victory opened Asia Minor to Alexander.

After marching along the southern coast of Asia Minor, Alexander and his army headed north to the city of Gordium. There, according to legend, Alexander found a wagon with an ox yoke tied by a tight, complex knot. An ancient prophecy said that whoever could untie this Gordian knot would become ruler of Asia. According to the most famous version of the story, Alexander first tried unsuccessfully to untie the knot and then drew his sword and cut it in a single stroke.

By 333 B.C., Alexander had reached the coast of Syria. There, in a fierce battle at Issus, he defeated the king of Persia, Darius III, but could not capture him. Alexander's army then marched south into Phoenicia to capture key naval bases at port cities. Part of one such city, Tyre, stood on an island about 1/2 mile (800 meters) offshore. Unable to capture the island from the sea, Alexander ordered his engineers to build a causeway out to the island, converting it into a peninsula that remains even today. His troops used such weapons as battering rams, catapults, and mobile towers in their attack. The Tyrians on the island surrendered in 332 B.C., after seven months of fighting. Alexander's use of huge siege machines at Tyre introduced a new age of warfare.

Alexander next entered Egypt. The Egyptians welcomed him as a liberator from Persian rule, and they crowned him pharaoh. On the western edge of the Nile Delta, Alexander founded a city in 331 B.C. and named it Alexandria after himself.

From Alexandria, the Macedonian king made a long, difficult trek through the Libyan Desert, a part of the Sahara, to the oasis of Siwah. He consulted the oracle of the god Zeus-Ammon, and, according to legend, the oracle pronounced Alexander the son of the god.

Alexander left Egypt in 331 B.C., traveling eastward into the Persian Empire. King Darius had formed a huge army that met Alexander's forces on a vast plain between the villages of Gaugamela and Arbela, just east of the Tigris River. The Persians far outnumbered Alexander's army, but Alexander's tactics and the training of his troops proved superior in battle. Darius was forced to flee, and he escaped across the Zagros Mountains into Media. This clash of armies, known as the Battle of Gaugamela or the Battle of Arbela, ended more than two centuries of Persian rule in Asia.

Alexander easily captured the fabled city of Babylon and then the Persian capital at Susa. In the winter of 331-330 B.C., Alexander's army marched to Persepolis. There he seized the royal palaces and captured a vast storehouse of gold and silver. Before leaving Persepolis, Alexander had his soldiers burn down the palaces.

In the spring of 330 B.C., Alexander swung north toward the Caspian Sea to find Darius. The Persian king could not gather enough troops to fight Alexander, and he was killed by his own nobles. The death of Darius left Alexander king of Asia.

Alexander moved his army into Bactria and then across the Hindu Kush mountains into Sogdiana, overcoming local military challenges as he went. In 327 B.C., Alexander married the Bactrian princess Roxane.

By 326 B.C., Alexander's forces had reached the upper Indus River Valley, in what is now Pakistan. Alexander wanted to continue east toward the Ganges River. But his homesick troops were tired of traveling and refused to follow him any farther eastward.

During his years in central Asia, Alexander began to adopt the customs of the Persian kings. Many of his troops resented this change. They considered their king a fellow warrior, not a godlike sovereign. Plots against Alexander's life appeared, and he executed several prominent Greeks and Macedonians who he believed had conspired against him. In a drunken brawl, Alexander killed his good friend Cleitus, who had saved his life at Granicus.

In 325 B.C., Alexander had ships built, and part of his army sailed westward from the mouth of the Indus River. These troops explored the northern shore of the Arabian Sea and the Persian Gulf. Alexander led the rest of his troops west across the Desert of Gedrosia. As many as half of his forces died on the way--more soldiers than enemy armies had killed.

Upon his return to Babylon, Alexander became busy with the administration of his vast domain, which stretched from Greece to the Indus. He probably intended to make Babylon his capital. Alexander planned new expeditions to northern Africa and Arabia. He tried to encourage trade and commerce and to develop a greater spirit of cooperation between Macedonians and Persians. He married a Persian princess who was a daughter of Darius, and he performed a mass marriage ceremony joining thousands of his soldiers to Persian women. Alexander also tried to incorporate large numbers of Persians into his army. But he failed to establish a stable kingship to maintain what he had won.

In the spring of 323 B.C., Alexander became seriously ill with a fever at Babylon. He also suffered from exhaustion and the effects of several battle wounds. He died at the age of 32 on June 10, 323 B.C. His body was placed in a glass coffin in a special tomb at Alexandria.

After Alexander died, his half-brother, Philip III Arrhidaeus, became king of Macedonia. At the time of Alexander's death, Roxane was pregnant with his son, Alexander IV, who later shared rule over the Macedonians with Philip. But Philip was murdered in 317 B.C., and young Alexander was killed about seven years later.

No one succeeded Alexander the Great in the rule of his vast empire. His leading generals became governors of various areas and fought among themselves for control of the empire. By 300 B.C., Alexander's empire had split into a number of independent states. The three most powerful states were led by Alexander's generals Antigonus, Ptolemy, and Seleucus.