Kweku Adoboli brought Swiss bank UBS to its knees by exceeding his trading limits and failing to mitigate the risk of reckless deals.
At one point the 32-year-old was on the verge of causing losses of $12bn (£7.5bn), and the hole he eventually left was the largest trading loss ever in British banking history.
Yesterday, jurors at Southwark Crown Court found him guilty of two counts of fraud, but cleared him of four counts of false accounting.
Sentencing, Mr Justice Keith told him: "Whatever the verdict of the jury you would forever have been known as the man responsible for the largest trading loss in British banking history."
Former public school boy Adoboli wiped away tears as he sat in the dock, following his nine-week trial.
He admitted the losses but claimed he was pressured by staff to take risks, culminating in a catastrophe that wiped £2.8bn off the bank's share value.
Mr Justice Keith said there were no other realistic verdicts open to the jury on the fraud charges apart from guilty. However, he was sceptical his acquittal on the four charges of false accounting meant he was innocent, only that the jury had doubts over whether he planned to gain financially himself.
He told the disgraced trader they "remain part of the picture of what your fraudulent trading involved".
Adoboli received seven years for a charge of fraud by abuse of position relating to the £1.4bn loss, and four years for a second count of the same offence, to run concurrently.
Andrew Penhale, deputy head of fraud at the Crown Prosecution Service, said: "The amount of money involved was staggering, impacting hugely on the bank but also on their employees, shareholders and investors. This was not a victimless crime."