The number of Europeans joining the Syrian jihad is not as high as some fear, but their impact on the war and potential threat upon returning home could be disproportionately great.

In recent weeks there has been much alarm about European Muslims joining the Syrian rebels. A report in the UK’s Independent claimed that more than 100 Britons have gone to Syria; Le Figaro gives an estimate of 50-80 people from France; Der Spiegel talks about “dozens” of Germans; and Jyllands-Posten mentions 45 Danes. The Netherlands even raised its terrorism threat level to “substantial” based on worries that — of the 100 or so individuals who are believed to have travelled to Syria — some may return to Holland and become involved in terrorist attacks.

This ICSR Insight provides a first full empirical assessment of how many Europeans have joined the rebels in Syria. It shows that the extent to which the Syrian conflict has mobilised Muslims across the world is significant: between 140 and 600 Europeans have gone to Syria since early 2011, representing 7-11 per cent of the foreign fighter total. European security services are well advised to adopt an intelligence-led, highly discriminate approach towards dealing with returning fighters.


Our estimate is based on more than 450 sources in the Western and Arab media as well as the martyrdom notices that have been posted in jihadist online forums. As with previous conflicts, the picture is far from complete and will probably remain so for years to come. There is no “true census” of foreign fighters, and publicly available sources are inevitably incomplete.  As a result, the figures range considerably. The numbers used on the lower end are conservative estimates/fully confirmed individuals, while the ones at the higher end include generalized (yet unverified) estimates provided by government and media sources. The data has been analysed in three different ways: (1) overall numbers in total or country-by-country, including those that are present, have been killed and/or arrested, or returned home; (2) the current presence of foreign fighters (March 2013); and (3) numbers confirmed killed when fighting with jihadist groups.

(1) Overall

Since the beginning of the conflict in Syria in early 2011, we estimate that around 2,000-5,500 foreign fighters have gone to Syria to fight with opposition forces. The European share of this total represents 135-590 individuals, or 7-11 per cent of the foreign fighter total.

On a country-by-country basis, the figures are as follows:

* Albania: 1

* Austria: 1

* Belgium: 14-85

* Britain: 28-134

* Bulgaria: 1

* Denmark: 3-78

* Finland: 13

* France: 30-92

* Germany: 3-40

* Ireland: 26

* Kosovo: 1

* Netherlands: 5-107

* Spain: 6

* Sweden: 5

(2) Current Presence

Based on the conflict totals, we estimate that 70-441 Europeans are still currently present in Syria. This suggests that most of the Europeans who have travelled to Syria are still on the battlefield.

Country-by-country, the figures are:

* Belgium: 4-75

* Britain: 17-77

* Denmark: 3-48

* Finland: 12

* France: 9-59

* Germany: 1-37

* Ireland: 15-25

* Netherlands: 4-104

* Spain: 1

* Sweden: 3

It should be noted that some of the sources may be dated, which means that the actual figures could be lower.

(3) Jihadist “Martyrs”

The rebel forces in Syria can be divided into three groups: independent local units; those aligned with the Free Syrian Army (FSA); and so-called jihadists whose ideology is linked to that of al Qaeda. Deaths in the third category — the jihadists — can be established via so-called martyrdom notices in al Qaeda-authenticated online forums.

Out of 249 foreign martyrdom notices, we have identified 8 (about 3 per cent of the total) whose country of origin is European. They include one from each of the following countries:

* Albania – * Britain – * Bulgaria – * Denmark – * France – * Kosovo – * Spain

* Sweden

The actual figures could be higher because of missed notices, or unreported deaths.


The Syrian government has — at various times and for different reasons — claimed that many fighters that are involved in the current conflict are foreigners. Our numbers do not support this assertion.

Even when juxtaposing the most liberal estimate for the number of foreign fighters over the course of the entire conflict (5,500) with the most conservative estimate for the current size of rebel forces (60,000), foreigners would represent less than 10 per cent. The actual figure is likely to be lower.That said, the foreign fighters’ impact and military value may be disproportionate when compared to locally recruited forces, given that foreigners are more likely to have been involved in conflicts like Libya and Iraq and, therefore, bring experience and skills that the locals don’t have.


Many news outlets and analysts frame all foreign fighters as terrorists or al Qaeda-aligned. The reality is more complex. As mentioned above, not all rebel forces in Syria are jihadist in orientation, nor are all the jihadist groups linked to al Qaeda. Furthermore, not everyone who has joined a jihadist group has been motivated by a fully formed jihadist worldview.The most commonly cited reasons for joining rebel forces are the horrific images of the conflict, stories about atrocities committed by government forces, and the perceived lack of support from Western and Arab countries. In many cases, these individuals fully adopt the jihadist doctrine and ideology only when they are on the ground and in contact with hardened fighters.


It is important to be nuanced when discussing the foreign fighter phenomenon in Syria: not everyone who has joined the Syrian rebels is al Qaeda, and only a small number may ever become involved in terrorism after returning to Europe.

That said, it would be wrong to conclude that individuals who have trained and fought in Syria pose no potential threat. Numerous studies show that individuals with foreign training and/or fighting experience have featured prominently in European based terrorist plots. Furthermore, according to a recently published study by the Norwegian academic Thomas Hegghammer, terrorists with foreign experience are far more lethal, dangerous and sophisticated than purely domestic cells.

The extent to which the Syrian conflict has mobilised Muslims across the world is significant and may be compared to the conflicts in Iraq in the 2000s, Bosnia in the 1990s, and Afghanistan in the 1980s. Based on the sheer scale of recruitment that is currently taking place, European security services are well advised to monitor the situation closely and adopt an intelligence-led, highly discriminate approach towards dealing with returning fighters.

Aaron Y. Zelin is the Richard Borow fellow at The Washington Institute.