The long awaited Chilcot report published in the last few minutes says when Britain went to war in Iraq in 2003 "there was no imminent threat from Saddam Hussein".
It also concluded that when the then Prime Minister Tony Blair presented evidence to parliament on weapons of mass destruction he did so "with a certainty that could not be justified".
26 Midlands families lost loved ones in the conflict that claimed the lives of 179 British service personnel.
The report is equally damning on what it describes at the 'failures ' in the planning and preparation for war and for its aftermath. It says soldiers were ill equipped to deal with the scale of the task.
150,000 Iraqi civilians died in the civil war that followed the invasion by American and British troops.
The report says in the run up to the war far too much reliance was placed on intelligence that should have been "challenged".
It says the tactics of Tony Blair were to emphasise the threat which Iraq might pose rather than make a "more balanced consideration of both Iraq's capabilities and intent".
However in relation to what became known as the 'dodgy dossier' of September 2002, Chilcot concludes "there is no evidence that No 10 improperly influenced the text".
It says the key lessons to be learned are the importance of collective Ministerial discussion and debate and the need to ensure that both the civilian and military arms of government are properly equipped for their tasks.
The families of those who died in Iraq will give their reaction shortly.