...I find it frustrating and a bit perplexing how the trappings of medieval culture have been appropriated by avowedly racist elements.
I get that there is a tendency to romanticize the crusades among people who are concerned about the growth of Islam in the West and in particular the recent influx of migrants from Syria. But the crusades were an expensive failure and were motivated less by religion and more by a need to create busy work for a class of professional soldiers and military engineers (sound familiar?).
The situation in Europe in the 11th and 12th centuries saw the Vatican in a predicament: they were concerned about the number of Christians killing other Christians because it was bad for the church to be against itself. The problem is, after the fall of the Roman empire Europe was run by a caste of warlords who were eager to fight each other and the hired mercenaries they paid to join them on campaign. When peace was attempted between kings and lords, these mercenaries had no one to pay them and took to plundering towns and villages to earn their living (if that's all you know how to do to support yourself, what choice do you have?). The Crusades were supposed to be an answer for that, but right from the get-go it backfired; each wave of crusaders headed toward Jerusalem plundered predominately Christian towns in their wake.
What's more, people got obscenely rich in the wake of the crusades. Many of the religious orders of knights became international monopolies that spanned Europe and Asia Minor all the way to Jerusalem. The Knights Templar became one of the first international banks, and they made a staggering fortune protecting pilgrims and their assets on the long trip to Jerusalem. They held a monopoly on banking, much like the Knights Hospitallers held a monopoly on the hospitality industry for pilgrims. This led to an upset in the balance of power in Europe that ended with the bloody destruction of the Knights Templar when the King of France decided to seize their assets for his own (whether or not there was any truth to the heresy allegations is still debated by historians). They certainly don't appear to be the best symbol of European identity for those who feel that speculators and bankers are partly to blame.
As far as how people actually related to each other during that period, most of the disputes arose not over matters of race, but religion. People of color traveled freely throughout Europe, married European women, and became fully assimilated if they converted to Christianity. By contrast, in modern times in the West, the outward physical manifestations of race became a much bigger obsession with the rise of "scientific" racism in the 19th century. It is safe to say that while something akin to what we call racism has always existed to a point, racism as we know it is a thoroughly modern invention.
And yet, the idealization and projection of values onto the racial and religious policies of the Middle Ages has become pervasive. Look up "Templar" on YouTube and you'll find plenty of channels that either contain or are subscribed to Neo-Nazi movements. At times it's frustrating because there is a real worry that because I respect and understand that history as part of my heritage, I'll be mistaken for a Neo-Nazi. If anything, what I really want to do is re-appropriate that heritage and its many, often-painful lessons, from those who would use it for hate and shine a light on just how badly the modern mind has misinterpreted our past to many nefarious ends. I want to chart a holistic social and philosophical path forward for Western civilization by building on the past rather than trying to resurrect or discard it wholesale. I certainly don't want to repeat the mistakes of the modern era and I regard racism as one such mistake.