In reality, the Prussian Crusade was not one, but a series of military campaigns conducted by Roman Catholic Crusaders. These campaigns were led by the Teutonic Order and their official objective was to Christianize under duress the pagan “Old Prussians”.
Invited after earlier unsuccessful expeditions against the Prussians by Christian Polish kings, the Teutonic Knights began campaigning against the Prussians, Lithuanians and Samogitians in 1230.
By the end of the 13th century the Teutonic Knights established not only an all but total control over Prussia, but a unique “monastic” state. This state was (understandably) called (in German) Staat des Deutschen Ordens, Deutschordensstaat or simply Ordensstaat.
Using this state as a powerful instrument (a combination of physical and ideological force), the Knights eventually completely erased the Prussian language, culture, their pagan religion… and ultimately the whole Prussian people (nation).
Thus achieving the practically total Christianization and Germanization of the Prussian region located on the south-eastern coast of the Baltic Sea, ranging from the Gulf of Gdansk in the west to the end of the Curonian Spit in the east and extends inland as far as Masuria (a region in northeastern Poland, famous for its 2,000 lakes).
Heinrich Himmler was born and raised in a conservative and devout Catholic family (where the subject of Catholic history was taken very seriously). It is also a well-established fact that he was obsessed with the vision and the ideals of medieval knighthood (and of ancient and medieval Germandom).
Hence it is no surprise that he was fascinated by the Teutonic Order and used it as a model (a starting point actually) for his very own quasi-religious order of “Black Knights”. The SS.
The SS inherited from the Teutonic Knights both its initial objectives (protection of the “common people” of Aryan blood from both criminals and “alien races”) and conquest of Lebensraum – with the subsequent “Germanization” (via resettlement of Germans and indoctrination of the native population) and either enslavement, deportation (thousands of Prussians were forced by the Order to flee to neighboring Lithuania) or physical extermination (Prussians who refused to convert to Christianity were ruthlessly massacred).
And so were the Jews – albeit not by Teutonic Knights, but by mobs of German Crusaders in Germany proper in 1096 (the so-called “Rhineland massacres”). In Jerusalem, the victorious knight Godfrey de Bouillon (one of the leaders of the First Crusade) found all the Jews conveniently assembled in a synagogue.
He burnt it down and burned the Jews to death. It is estimated that upwards of 10,000 Jews were murdered in Europe during the First Crusade, constituting a third to a quarter of the Jewish population of the continent.
Another critically important structure inherited from the Teutonic Order by the SS was the idea of the Ordensstaat – a distinctive state based upon the religion and ideology.
Essentially, the SS became the SS-Staat – initially the “state within a state” (i.e. within the Third Reich – much like the Ordensstaat was a state within the First Reich – the Holy Roman Empire). However, Himmler’s ultimate objective was to acquire the absolute power in Germany and then use this power to transform the Führerstaat (the Third Reich) into the SS-Staat (the Fourth Reich of sorts).
However, there were (obviously) several crucial differences between the Teutonic Order and the SS. First, the Teutonic Knights were a Christian Order while the ideology of the SS was based on a neo-pagan quasi-religion (more on that later).
The insignia of the Teutonic Knights was Christian – a black cross on the white garment while the SS insignia was decidedly pagan (German runes). Actually, from the religious perspective, the SS was the “Teutonic order in reverse” – while the fundamental objective of the Knights was to convert pagans to Christianity, the objective of the SS was exactly the opposite – convert Christians to neo-pagan quasi-religion.
Second, The Teutonic Order was a monastic one – its members took the vow of celibacy and were not supposed (to put it mildly) to father children. Heinrich Himmler (unlike modern liberal politicians and leaders) was aware of the inevitable “war of the civilization” and (ditto) knew that victory in this genuinely existential war boiled down to fertility rates (the higher, the better).
Hence, SS members were required to (1) get married; and (2) produce the maximum possible number of children – both “legitimate” and “illegitimate” (provided, naturally, that in both cases mothers were of “pure Aryan blood”).
And, finally, the Teutonic Order never intended to take over a country (let alone of the whole European Civilization) while the ultimate objective of the SS was exactly that.