The European Court of Human Rights has ruled that British troops in Iraq were bound by human rights law.
Judges at the Strasbourg court said soldiers overseas were bound by the European Convention on Human Rights.
Britain argues that the convention do not apply to troops based outside Europe.
Four years ago, the House of Lords ruled there was no UK human rights jurisdiction surrounding the deaths or wrongful detention of six civilians.
The BBC reports the latest judgement effectively extends the remit of the convention.
The judges said that in the ''exceptional circumstances'' when UK forces assume responsibility for security in parts of Iraq, they remained under rules obliging signatory member states to safeguard the right to life and liberty.
Lawyers representing those who brought the case said it was a ''historic day'' for human rights in Europe.
In a statement, Public Interest Lawyers said:
''The immediate ramifications for the Ministry of Defence are highly significant.
''The court's ruling means that a whole host of Iraqi victims, previously prevented from accessing justice, are now finally to seek redress for their abuse.
''For the first time, they will be able to go to the High Court in London and force the Secretary of State for Defence to order a public inquiry into the actions of British soldiers in their cases.''
The cases before the court all involved incidents between May 203 - June 2004 when Britain was an occupying force in Iraq.
Three men were shot dead or shot and fatally wounded by British soldiers during patrols or raids, and another died during an exchange of fire between a UK patrol and unidentified gunmen.
A fifth was allegedly beaten and forced into a river where he drowned. The sixth was seized by members of the 1st Battalion The Queen's Lancashire Regiment.
He was taken to a British military base where he was beaten and died of asphyxiation with 93 injuries on his body.
The seventh is a British and Iraqi national now living in Istanbul.
He was arrested in October 2004 on suspicion of terrorist involvement in Iraq, and held in a detention centre in Basra run by British forces for three years without charge.
The relatives of those who died, except one, were awarded £15,200 (17,000 euro) each in damages and a total of £44,700 (50,000 euro) in costs and expenses.
The BBC reports the court ordered the UK government to pay the seventh man damages of £22,400 (25,000 euro) and £35,700 (40,000 euro) in costs and expenses.