The word "Punjab" for the first time was mentioned in the Book ``Tarikh-e-Sher Shah'' (1580) which mentions the construction of Fort by a fellow named ``Sher Khan of Punjab''. Again the name is mentioned in ``Ain-e-Akbari'' part 1 written by Abul Fazal who also mentions that the territory of Punjab was divided into two provinces of Lahore and Multan. Similarly in the second volume of ``Aeen-e-Akbari'' title of a chapter contains the word ``Punjab'' in it. Also the Mughal King Jahangeer mentions the word ``punjab'' on page 183 of his book "Tuzk-i-Janhageeri". [Quraishee 73] But Archeologists have traced the signs of human habitation to times long before that of Mughals arrival. The upper basin of Indus and the Baluchistan Plateu hosted one of the earliest human civilizations known as the Indus valley civilization. The earliest signs of life human activity date as far back as 7000 B.P. The Indus valley civilization grew from small village and settlements to highly refined urban life. At its height, around 3000 B.C., it boasted the splendid cities of Harrapa (Near present Day Sahiwal in West Punjab) and Moen-jo Doro in the lower Indus valley. The story of the decline, whose reasons are still not completely explained, of civilization is also told through the remains of these cities. Aryan Migrations: Among other reasons like the change in the wheather patterns, urbanization without any rural agricultural production base one factor is reported to be the series of raids or small scale migrations by the Aryans from the North-West (1500-100 BC). The next thousand year history of Punjab (or Arya-Varta, the land of Aryas, as Aryas called it) is dominated by the Aryans and their interactions with the natives of the Indus basin. Here is where the oldest books of human history called the Rig-Vedas are supposed to have been written. The Aryan tongue Sanskrit became a symbol of the Aryan domination of the area. Easternmost Satrapy of the Persians: Punjab lied at the outskirts of the great Persian empires and came under their control from time to time. The Persian King Darius the great is reported to have attacked Punjab and occupied some parts. But for the first time the coccupation of Punjab was completed by the Persian King Gustasp in 516 BC. Punjab became the wealthiest Satrapy i.e., the province in the Persian kingdom. Greeks, the rival empire of the Persians, also had some knowledge of the area. The great Persian Emperor Darius I (521-486 BC) appointed Skylax the Greek to explore the area around Indus river for commercial expeditions who provided an account of his voyage in his book ``Peripulus''. Hectaeus (500 BC) and Herodotus (483-431 BC) also wrote about the ``Indian Satrapy'' of the Persians. Alexander's expeditions were documented in the works of Strabo, Ptolemy, Pliny, Arrian and others. They described a region that had plenty of mighty rivers and was divided into four Kingdoms. In Greek maps we find the mention of the mightiest of river of all the world called the Indos (Indus) and its tributaries of Hydaspes (Jehlum), Akesines (Chenab), Hydroatis (Ravi), Hyphasis (Satluj) and Hesidros (Beas). Alexanders's Invasion: In 321 BC Alexander the great after breaking the might of the Persians entered their final Satrapy of Punjab. He invited all the cheiftans of this Satrapy to come to him and submit to his authority, which is exactly what the ruler of the northwest most (west of Hydaspes) kingdom of Gandhara with its capital of Taxilai did. But the ruler of the Kingdom beteen (Hydaspes and Akesines) refused to submit to Alexander's authority and the two armies fought the historical battle on the bank of Akesines outside the town of Nikaia (somewhere around modern city of Jehlum). Porus put up a tough fight but his army was no match for Alexanders army. After losing his sons and getting hurt himself when the defiant Raja was brought in front of Alexander, the legendary conversation took place when Alexander inquired Porus, ``How should I treat you?'', the brave Porus shot back, ``The same way as a king treats another king.''. Alexander was struck by his genius and he not only returned the Kingdom back to Porus, but he also added the area lying between Akesines and Hydraotis to his Kingdom whose ruler had fled. Alexander as with his other occupied areas established two cities in the area of Punjab, where he settled people from his multi-national armies which included a majority of Greeks and Macedonians. These cities along with the rule of the Indo-Greek thrived long after Alexander's departure. Alexander's Eastern empire (from Syria to Punjab) was inherited by Selecus Nicator, the founder of Seleucid dynasty. However the Greek empire in the east was disrupted by the ascendency of the Bacterians. The Bacterian King Demetrius I added Punjab to his Kingdom in the second century BC. The best known of the Indo-Greek kings was Menander who established his independent kingdom centered at Taxila in 170 BC. He later moved his capital to Sagala (The modern Sialkot). Menander soon captured territories east of his kingdom and grew to rival the power of Bacterians. Menander died in a vain attempt to conquer Bacteria in 130 BC. Menander's successors maintained the their rule on Punjab till 55 BC when the whole area was disrupted by the events happening in greater Euro-Asia. In the middle of the second century BC, Yui Chi tribe of modern China began to move westward which caused in turn to Sakas or Scythians to move. Northern Sakas successfully wrestled the power of the areas from the Indo-Greeks. Another Central Asiatic people to make Punjab their home were the white Huns who made continuous campaigns towars this part of the world. Finally establishing their rule in the later 3rd century AD. Muslim Invasions Following the birth of Islam in Arabia in 6th century AD, Arabs rose to power and replaced the Persians as the major power in the area. In 711-13 AD Arabs advanced to the land of five rivers, occupying Multan. Further north the area that survived the Arab attcks was divided into small kingdoms. Meanwhile in Ghazni after the death of Subuktgin, the Turk, his son Mahmud assumed power in 997 AD. He was to expand his father's kingdom far to the west and east of Ghazni through his military conquest. He was to attack Punjab 17 times during his reign. The Ghaznavids were uprooted by the Ghauris who extended their rule as far as Dehli. Shahabuddin Ghauri annexed Lahore to his kingdom in 1186. After Ghauri's death his governor Qutbudin Aibak became an independent ruler of Punjab and founded the Mamluk sultenate. Khiljis' replaced the Mamluks in 1290. The rule of Khiljis was briefly disrupted by the two successful raids by the Mongols who marched their way to dehli twice during Alauddin khilji's rule. tughluqs succeeded Khiljis in 1320 AD. Tughluq rule was replaced by the Sayyids in 1414 AD. Lodhis gained control of Dehli in 1479 AD.