The first soldiers to leave the country boarded a plane for the UK — after command for the Basra garrison was transferred to the United States.
They included the now former British forces boss, Major General Andy Salmon.
A total of 179 British military personnel were killed and 1,000-plus wounded — the majority by Iran-backed militants — since the toppling of Saddam Hussein in 2003.
The rest of the 4,100-strong force will pull out over the next two months — with PM Gordon Brown setting the official end-of-combat date in Iraq as May 31, with all fighting troops out by July 31.
Top brass from London and Washington jetted into the Basra air base for the occasion.
Britain’s most senior warrior, Air Chief Marshal Sir Jock Stirrup, lead the tributes. Chief of the Defence Staff Sir Jock said: “We remember those who paid the ultimate price in this endeavour, those who suffered injury and disablement in order that we might get to this point today.”
He added: “This occasion is about the countless numbers of young men and women from the United States, from the British Isles, who have striven with such dedication, with such commitment and with such courage.
“It’s about the effort they put in, it’s about the difficulties they overcame, it’s about the losses they suffered.”
Iraqi military boss General Nasier Abadi told yesterday how now stable Basra had been “transformed” thanks to the immense sacrifices of UK forces.
Gordon Brown called the handover “a further step forward in the UK’s work in Iraq”. He said there had been difficult times but British troops “have made an outstanding contribution”.