ISLAMIC STATE HAS become notorious around the world for its brutal violence – including mass killings and beheadings – in the space of less than 18 months.

In that time, it has risen from regional force to global threat.

Barack Obama, before the Paris terror attacks on Friday, said that the militant group’s geographic expansion in Iraq and Syria had been contained.

Today, faced with an utterly changed geopolitical landscape in the wake of the carnage in Paris, the world’s major powers have been setting out their coordinated response to the violence, which has been claimed by IS.

Obama has declared it as an “attack on the civilised world” – and Russian president Vladimir Putin said that the tragic events in Paris showed the global community needed “to unite our efforts in fighting this evil, something we should have done a long time ago”.

So what are the roots of the group?

And how has their influence and capability grown in the year-and-a-half since they first became widely known outside of Iraq and Syria?

Tributes at the Le Petit Cambodge in Paris, following the terrorist attacks on Friday evening. PA WIRE PA WIRE

Islamic State – its roots and aims 

The main aim of the group is to establish a ‘caliphate’.

The idea of a caliphate – which is, roughly-speaking, the creation of a holy land for Muslims under the leadership of a ‘caliph’ – dates back to the seventh century, after the time of the prophet Muhammad’s death. Isis has resurrected the idea.

The militant group has existed in various forms since 1999 and was originally an Iraq-based affiliate of al-Qaida.

Islamic State’s current leader Abu Bakr Al-Baghdadi – who was born in Iraq in 1971 – took over in charge in 2010.  

Abu Bakr al-Baghdadi, speaking in Mosul in 2014.

In 2013 Islamic State in Iraq changed its name to Islamic State in Iraq and the Levant – becoming known as Isis or Isil around the western world. In Arabic, Islamic State is known as Daesh.

Al-Qaida formally ended its affiliation with the group in February of 2014, having become frustrated with its independence and brutality, according to Bloomberg.

Al-Baghdadi claims to be a direct descendent of the prophet Muhammad. The US State Department has a bounty of $10 million on his head.

How much territory does it hold? 

The group took control of the western Iraqi city of Fallujah in September 2012. It began to advance across eastern parts of Syria the following spring – seizing oil wells and collecting taxes to fund its war effort as it continued its attacks.

Islamic State militants took control of Raqqah in 2014, and the Syrian city has since become the group’s de facto capital.

IS extremists seized control of Iraq’s second biggest city, Mosul, in June of last year – sending troops and residents fleeing. Members of the Iraqi military reportedly abandoned their posts as the Isis fighters advanced.

A US Department of Defense map of Isis territory from April of this year. US Department of Defense US Department of Defense

According to the BBC, then-director of the US National Counterterrorism Center (NCTC) Matthew Olsen, said in September of 2014 that Islamic State controlled much of the Tigris-Euphrates river basin – an area similar in size to the UK.

Some 25% to 30% of Iraqi territory had been taken back from Islamic State by April of this year, the US defence department said. However, its territory in Syria remained largely unaffected.

How has it built its power? 

Islamic State’s reputation for violence and brutality spread online and via traditional media from the summer of 2014.

A series of horrific killings were carried out by the group – many presided over by the masked militant known as ‘Jihadi John’ (Mohammed Emwazi – he was the target of a US drone strike last Thursday and is now believed killed).

Still image from an Islamic State video.

Among those beheaded by Islamic State in videos posted online since August 2014 were US journalists Steven Sotloff and James Foley, US aid worker Abdul-Rahman Kassig, British aid workers David Haines and Alan Henning, and Japanese journalist Kenji Goto.

In the videos, a tall masked figure clad in black and speaking in a British accent typically began one of the gruesome videos with a political rant and a kneeling hostage before him, and ended it holding an oversize knife in his hand with the headless victim lying before him in the sand.

IS militants have shown themselves to be sophisticated users of social media – and are reported to have recruiters all over the western world seeking out new fighters.

A number of other groups have also pledged allegiance to Islamic State, effectively creating ‘franchises’ – including Nigeria’s Boko Haram, as well as groups in Libya and on Egypt’s Sinai Peninsula.

Traditional advances also continued across Iraq and Syria – including May’s capture of the ancient city of Palmyra. Ramadi, the capital of the western Iraqi province of Anbar, also fell to Isis in spring of this year – months after Iraqi forces retook the city of Tikrit, backed by airstrikes.

Many of its weapons are simply captured from its enemies in the battlefield. However, the group has also had strong support from within a number of Gulf countries. War reporter David Axe told Public Radio International last year that Isis, like all Syrian opposition groups, has enjoyed support from individuals within Turkey, Qatar and Saudi Arabia.

“What ISIS wants, to some extent, overlaps with what certain powerful people in some of these Gulf states want, which is, for lack of a better word, a ‘Sunni-stan’ — a homogenous Sunni Muslim state in what is now Syria and Iraq,” Axe said.

Who is fighting them? 

The US began airstrikes against IS in Iraq in August of 2014. Coalition airstrikes on territory in Syria – including Bahrain, Jordan, Saudi Arabia and the UAE – began the following month.

Associated Press Associated Press

Britain has been involved in strikes on Iraqi territory but not in Syria. However, speaking earlier this month foreign secretary Philip Hammond said the country expected to escalate its campaign against Isis into Syria as soon as a consensus could be reached in Parliament. 

France carried out its first air-strikes against Islamic State in Syria in September of this year - destroying a training camp in the eastern town of Deir al-Zour. Like the UK, the country had previously confined its strikes to Iraqi airspace.

Backing Syrian President Bashar al-Assad, Russia entered the Syrian civil war at the end of September this year – targeting rebel groups backed by western leaders, as well as Islamic State.

An RAF Reaper UAV. PA WIRE PA WIRE

Why are people talking about a ‘new phase’ of violence?

While there has been no hard evidence as yet, it’s highly likely Islamic State’s affiliate in Egypt was behind the bombing of a Russian passenger jet over the Sinai desert, which crashed killing all 244 people on board last month.

It’s believed a bomb was placed in the plane’s hold before take-off. 

“The Sinai attack would be a first, and would signal that the Islamic State has become both capable of — and interested in — joining the dreadful ranks of global terrorism,”  an analysis by the Soufan Group, a private geopolitical risk assessment company, found.

A Russian investigator walks near wreckage of the downed plane. Associated Press Associated Press

Isis were also blamed for two suicide bomb attacks that killed 100 people attending a pro-Kurdish rally in the Turkish capital, Ankara, on 11 October.

The group also claimed responsibility for twin bombs that killed 44 people in Beirut on Thursday of last week.

Friday’s events in Paris confirmed that Islamic State’s campaign of violence and terror had “gone global”, according to the analysis of many commentators.

How will the world respond? 

France has already responded to Friday’s attacks with a series of “massive” airstrikes on Isis stronghold Raqqa.

World leaders have also vowed to boost intelligence sharing, cut off terrorist funding and strengthen border security in Europe as they seek to show unity in the wake of the Paris attacks.

While US officials said President Obama viewed the attacks in France as an act of war, they cautioned he had no plans to overhaul his strategy for dismantling Islamic State.

The President later said it would be a mistake to send US troops into a ground war.

Special intervention forces sit on top of a roof as they prepare to enter a house in Brussels today. Associated Press Associated Press

Meanwhile, a crackdown on suspected accomplices of the Paris bombings has been continuing in France and Belgium.

French police carried out nearly 170 searches and arrested 23 people in raids overnight, and 104 people have been placed under house arrest over the weekend.

The Belgian Abdelhamid Abaaoud – a child of Moroccan immigrants – was today named by French authorities as the suspected mastermind behind the Paris attacks.

With reporting from Associated Press.

(Updated at 4.30pm to include detail on where Isis gets weapons and support – following a number of queries – DB)

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