Oldest complete history of a nation?

Question

what is the oldest known complete history of a nation?

Answer 1

The Bible chronicles the history of the people of Israel since time began.

Answer 2

There is no "complete" history of any nation.  There are partial histories that date back for centuries, but they are usually limited to genealogies.  

Winston Churchill wrote "A History of the English-Speaking Peoples" which begins with the Roman invasion in 55 BC, but when did the British people become a nation?

There are oral histories in parts of Africa and Polynesia that follow genealogies back for hundreds of years.  

Herotodus wrote  "Historia" in the 5th century BC as an inquriry into the origin of the Greco-Persian Wars.  The word, "historia," mean inquiry.  All of history is an inquiry into how things got to be the way they are (or were).  

In a sense, the old testament of the bible (torah) is a history of the people of Isreal.  It was an inquiry into how things went so terribly wrong that they suffered the Babylonian captivity and the diaspora.  

Part of the problem is that "nation" is not well defined.  It could mean a race (Hmong) a country (Monaco), or a culture within another country (Basque).  

Another problem is completeness.  A comprehensive history would have details of all of the minutiae.  Most histories are limited to genealogies, significant events, easily documented objective facts.  There are also social history, cultural history, political history, economic history, and technological history.  The treatment, content and interpretation of history depends on the writer's point of view and agenda.  

You would be best to seek several different writers and form your own opinions.