The centuries after Alexander's death are known as the era of Hellenism. One might argue Hellenism lasted from the years of Alexander's reign until 146 BC, when Greece was annexed by the Roman empire; or even until 30 BC, when the famous Greek-Egyptian Queen Cleopatra died, the last Hellenistic ruler. In any case, Hellenism was the new world order shaped by Alexander's conquests.
The campaigns of Alexander had opened up gigantic areas to world trade and economic development. The conquering Greeks had aroused the sleeping masses of the east and profitable industries and agricultural enterprises sprung up everywhere. Because Alexander had started to mint the gold reserves of the Persian kings, huge amounts of money came into circulation. For centuries the Persian dynasts had safeguarded the treasures stored in their palaces. Alexander tried to spend them all within a matter of years.
These factors combined, Hellenism can be seen as the world's first major economic boom. The system of economics and trade that developed after Alexander's death would remain basically unchanged for over two thousand years, until the industrial revolution of the 19th century. When the Romans began to expand their empire around 200 BC they inherited a world of florishing trade contacts for which Alexander had laid the foundations.
As world population was rapidly growing, the Hellenistic era saw the rise of new Greek cities everywhere - from cosmopolitan Alexandria in Egypt to the cultural melting pot of Taxila in present day Pakistan. The Seleucid dynasty, successors of Alexander in Asia, was the biggest city founding monarchy in history. Most Seleucid cities bore the names of their kings, like Seleucia and Antioch, or of their queens, like Apameia. Egyptian Alexandria, on the crossroads of trade routes and the principal city of Hellenism, had one million inhabitants. Seleucia, the first Seleucid capital in Mesopotamia, had half a million.
Though Hellenistic cities were centers of trade, science and arts, life was not a bed of roses. The Hellenistic world was a very capitalistic society with huge gaps between the rich and the poor. While the cities offered splendour and luxury for the wealthy, large portions of the population lived in absolutely miserable conditions. Especially in Alexandria riots were common.
After Alexander's death five empires of his successors competed for domination: Macedonia, the Antigonids of Asia Minor, the Seleucids of Asia, the Ptolemies of Egypt and the Thracian empire of Lysimachos. It seemed Antigonus was the most powerful of the new kings, but he was defeated at the battle of Ipsos in 301 BC. This 'Battle of the Kings' put an end to all hopes of a reunification of Alexander's domains.
From then on the Hellenistic world was divided in three parts: the Egyptian empire of Alexander's general Ptolemy, the richest and most stable of the kingdoms; the gigantic empire of Alexander's officer Seleucos, streching from the Aegean to Central Asia, which slowly crumbled to pieces over the centuries; Macedonia, which, although the smallest and poorest of the empires, was still prestigeous as Alexander's motherland.
The arts florished in the Hellenistic world - especially painting, sculpture and architecture - although the emphasis was on quantity rather than quality. The harmonic principles of earlier Greek art were neglected. More works of art were produced than ever before, but few of them were masterpieces and 'bombast' ruled.
On the Greek island of Rhodes the Colossos was erected, a gigantic statue guarding the harbor. It was said the arms of a man could not embrace even a finger of the Colossos. The statue was destroyed in an earthquake in 225 BC. This monstrosity would have been surpassed if the sculptor and architect Dinocrates would have had his way. His plan was to carve a 2,000 meter high statue of Alexander in the rocks of Mount Athos in northern Greece - sitting with its head in the clouds and its feet in the sea.
Just like with the arts, the emphasis in warfare was on 'more' rather than 'better'. The battles fought by the successors in the years after Alexander's death involved larger armies, heavier armor and bigger weapons. The Hellenistic commanders loved elephants. The Seleucids had traded their Indian possessions for 500 war elephants which they used to devastating effect at the battle of Ipsos. In retrospect, the years of Alexander's campaigns seem rather peaceful compared to the massive wars that raged afterwards.
The accent on army size and weaponry resulted in deterioration of training and tactics. The Hellenistic kings started to use double sized, heavily armoured phalanxes as their primary weapon of attack - whilst Alexander had used lighter phalanxes in a more defensive role. When the Romans wiped out the Macedonian forces at Cynoscephalae in 197 BC and Pydna in 168 BC the quality of troops and leadership was a mere shadow of the military standards achieved under Philip II and Alexander.
Science blossomed during Hellenism. The metropolis of Alexandria hosted the largest library of Antiquity with over 70,000 books and half a million scrolls. It was destroyed by a fire in 47 BC. The library of Pergamum in Asia Minor was a good runner up. Regarding geography, the British Isles were put on the map by the Greek navigator Pytheas. In 235 BC Erasthostenes measured the circumference of the earth by comparing the length of shadows in Upper and Lower Egypt. His calculations predicted the equator should be about 47,000 kilometers long. (The correct answer, as we know now, is 40,000 kilometers.)
Technical progress was enormous. New machines and instruments were invented. But the greatest genius of the era was Archimedes, the 'Einstein' or the 'Newton' of Hellensim. This Greek mathematician and psysicist, living in Syracuse on Sicily and famous for the discovery of the rules of density, is considered the most important scientist of Antiquity.
The concept of 'the Seven Wonders of the Earth' dates back to the Hellenistic period. These seven wonders were the principal landmarks of the world of Hellenism. The first three were the statue of Zeus in Olympia, the Pyramids of Egypt and the Hanging Gardens of Babylon. Connected by straight lines these three form a triangle indicating the economic heartland of the Hellenistic civilisation.
The next four were the Temple of Artemis in Ephesos, the Mausoleum in Halicarnassus, the Colossos of Rhodes and the Pharos (lighthouse) of Alexandria. They lay more or less in a straight line corresponding with the major trade route between Asia Minor and Egypt: the economic aorta of the Hellenistic empires.