The Islamic Center of San Diego on May18, a few hours after the shooting. Leonard LMT/Wikimedia Commons, CC BYOn Monday, May 18, two assailants, a 17 and an 18 year old, attacked the Islamic Center of San Diego, the site of both a mosque and school, killing three adults. The assailants were wearing Nazi SS insignia, and had the words “race war” written on their weapons.The attack underscores European history’s centrality to the global far right’s discourse and ideology. It was the latest deadly manifestation of the weaponisation of European history to justify violence in America in the present. But this is not just a US problem. Europe’s history was also explicitly referenced in the manifesto of the 2019 Christchurch shooter in New Zealand. The Christchurch attack was itself inspired by Anders Breivek’s 2011 attack in Norway, which was primarily motivated by a violent white nationalist worldview.These attackers all drew inspiration from Adolf Hitler and the SS to justify both antisemitic and Islamophobic violence. But within the white nationalist imaginary, European history begins much earlier. It extends to visions of a pure white race in the Greek and Roman eras, and to idolisation of historical figures such as Charles Martel, the Frankish leader who defeated a Muslim army in Tours in 732. Leer más: The enduring legacy of medieval Christian depictions of Islam in today’s political discourse It also leans heavily on the imagery of the European Crusades to retake the Holy Land, which began in the 12th century. The Knights Templar – the Crusade-era order of Christian warrior monks – has captured far-right popular imagination in Europe and the US, especially among the alt-right.Political actors across the spectrum invoke the past to grant legitimacy in the present and suggest inevitability in the future. But for far-right leaders, European history is especially easy to weaponise. It provides a ready-made set of memes, metaphors, images and tropes that legitimise hate speech – and hate crimes – in the name of protecting Christian Europeans from the perceived threat of Jewish and Muslim invaders.Warning signsIn 1992, I set foot in the Islamic Center of San Diego for the first time. As an undergraduate student at UC San Diego, I was there to announce that our Muslim Student Association was fundraising for the very first Bosnian Muslim refugees who were arriving in our county. We had to have this meeting because most of the congregation at the mosque had no idea there were even Muslims in the former Yugoslavia.Track forward to May 2026, two assailants used a camera to record their massacre in the Center and broadcast it on Discord, with the words “race war” etched onto their pistols. The practice of writing on firearms is not an isolated incident in the history of Islamophobic attacks, nor is recording them on video.In March 2019, an Australian-born man attacked two mosques in Christchurch, New Zealand. He killed 51 people and filmed his attack, broadcasting it on Facebook. The video is still in circulation on the internet today.The Christchurch attacker used five guns inscribed with the names of various European historical figures and battles against Muslims, as well as the racial slur “kebab remover”, a sinister euphemism for ethnic cleansing that is linked to the 1991-1995 Bosnian civil war. The phrase is an homage to Bosnian Serb leader Radovan Karadžić, the very warlord whose crimes against humanity led so many Bosniak refugees to flee the country – and many of those who reached the US settled in San Diego. It was Karadžić who conflated “kebabs” with the Bosniak Muslims, and “remove kebab” is still an Islamophobic meme among the European far right, where the continent’s ubiquitous kebab shops are often equated with Muslim immigration. Leer más: How Islamophobic rhetoric leaves an impact on the mental health of Muslim Americans The New Zealand attacker also etched battles from the Crusades on his weapons, and his online manifesto named Anders Breivik as his hero. Breivik detonated a bomb in central Oslo in 2011, killing 8 people before massacring 69 more. Breivik was obsessed with the medieval Crusades, dressing up as a Knight Templar in his own manifesto.The New Zealand neo-Crusader attack inspired two attacks in the US the following month. In April 2019, three members of a Kansas militia calling itself the Crusaders were arrested before they could carry out a plot to bomb an apartment complex housing Somali Muslim families and a mosque. In the same month, a 19-year-old student walked into a synagogue in northern San Diego County and opened fire on the congregation that was commemorating the last day of Passover, killing a 60 year old woman and injuring three others. This same attacker had previously tried to burn down a local mosque, inspired by the Christchurch shooting.This assailant was a nursing student at Cal State University San Marcos where I teach, and was studying in a building just across from my history department. He told students he admired Hitler, and his colleagues reported it to our administration, which failed to act on the warnings of his weaponisation of history. Leer más: San Diego mosque shooting reflects how online rhetoric, media depictions and political discourse contribute to increased Islamophobia Weaponised history legitimises violenceFollowing in the footsteps of the New Zealand shooter and the Cal State San Marcos shooter, both of the San Diego mosque shooters engaged in their deadly assault to motivate future copycat attacks. Their manifestos reportedly envision their shooting as inspiring a “crusade”. They even called themselves the “Sons” of the New Zealand attacker.On April 24 2026, I returned to the Islamic Center, not as a student, but as a history professor giving a community lecture. And as a historian, I was uniquely qualified to warn them that, based on my study of the history of past Islamophobia in our area and globally, there was an increased risk of violent attacks, including on the Center itself. Tragically, my fear became manifest just a few weeks later.In that lecture, I lamented that while Crusader history is ubiquitous, neither on my campus nor in the entire San Diego area is there a single class or program devoted to the history of both Muslim Americans and Arab Americans. This is a class I have been pushing and fighting for since 2012, when I permanently moved to the area. We can combat the radicalisation that stems from a racist, fantasised version of European history. We can do this by not just teaching classes on Europe’s military conquests and crusades, but also the rich, lengthy history of ordinary Muslims and Arabs coming to both the US and Europe, trying to make a better future for both their children and their newly adopted countries. A weekly e-mail in English featuring expertise from scholars and researchers. It provides an introduction to the diversity of research coming out of the continent and considers some of the key issues facing European countries. Get the newsletter!Ibrahim Al-Marashi no recibe salario, ni ejerce labores de consultoría, ni posee acciones, ni recibe financiación de ninguna compañía u organización que pueda obtener beneficio de este artículo, y ha declarado carecer de vínculos relevantes más allá del cargo académico citado.