Historians are timekeepers of history in a geographical region at a point of time not necessarily during their own life time. Hence their accountability is even greater than the rulers of that era for honesty, veracity and credibility. The sin of putting a lie in the mouth of time can be a crime against future generations for perpetuating falsehood even if it goes undetected. 

Abd-amar-Rahman Abu Zayd ibn Muhammad ibn Khaldun is among the pioneers of medieval age  chroniclers who made fundamental contribution to the study of history. Rational in approach, minute in detail and authentic in verification of data he never invented history to curry  favors with his patrons The MUUQADDIMAH is Ibne Khaldoun’s book on world history entitled KITAB AL-IBAR and remains classical work even after 750 years. This historic masterpiece of all times was written in 1377 when he was 45 years old. Imprisoned in 1357 following court intrigues he was reinstated as Vazier because of his scholarly stature among contemporaries and his record of administrative capabilities. 

At the CENTRE of his historiography is man in quest of his evolution and intellectual advancement. He discovered a pattern in the rise and fall of dynastic empires, cultures, communities and civilizations summed up in his monumental works in Arabic. He died in 1406 at the age of 74. His masterly vector analysis of development and decline of civilizations of yore is a landmark in historiography.

Firaq Gorakhpuri has brilliantly summed it up in his Rubai

In the vast wilderness of Time and Space Cultures are nurtured in  sublime  Grace; Oft I wonder in my reveries of solitude, Why do civilizations vanish without a trace?

Similar sentiment was vented by a Kashmiri Sapru Brahmin of yore, whose ancestors converted to Islam few generations earlier. In his highly patriotic poem of “Sare jahaan se Achha Hindustaan hamara ...”