Why did many Europeans "turn Turk," but few Turks turned European?

I am, as always, reading about pirates, and particularly the so-called “Barbary pirates.” Many of the famous Barbary pirates were in fact born European and Christian, like Aruj and Hezir (Kheireddin) Barbarossa. Simon de Danser is another famous example, a Danish prisoner of the Barbary corsairs who adopted Islam and introduced European sailing rigs to his captors around 1600, thus enabling them to raid into the Atlantic as far north as Iceland. The European who “turned Turk” was such a well-known figure that Rafael Sabatini wrote a novel, The Sea Hawk about an Englishman who joins the Barbary pirates.

But I don’t think I’ve ever heard of a Turkish (or Arab or Berber) prisoner of the Europeans who converted and terrorized his own people. Did such a thing ever happen? And if not, why not?

The only explanation that comes to my mind, a mere guess, is that there were just a lot more European slaves who had the opportunity to convert. If Davis’s Christian Slaves, Muslim Masters is correct, there were slightly over a million Christians, mostly European, enslaved by the Barbary corsairs over the course of several centuries. I don’t know how many Muslim slaves were taken by Europeans over the same period. Certainly the Knights Hospitallers took some, and then I guess the Spanish and Portuguese would have enslaved some portion of the populations of Ceuta, Oran, Tunis, Algiers, and other North African cities that they briefly controlled. Still, I am guessing that the total Muslim slaves captured by Europeans numbered substantially fewer than a million.

Another odd thing is that I haven’t heard of Europeans turning Turk after the early 17th century. Did “turning Turk” go out of fashion, and if so, why?

In their case, they weren’t. Both of them were born on Lesbos to a Turkish Muslim father and a Greek Orthodox mother, and raised in what’s now Greece, but was at the time, Ottoman territory. Their father was, in fact, one of the soldiers who had fought to capture Lesbos from Genoa, and had been given land in return for his service.

Maybe the Europeans wouldn’t have them, whereas the Turks weren’t quite so snobby?

I had previously only read that they were Greek Christians, but Wikipedia says you’re right.

Maybe Murat Rais the Younger and Uluj Ali would be better examples than the Barbarossas.

One could hypothesize that the relative social mobility in the Ottoman regime might explain things well enough, including openness to non-Muslims in state service. How many Christian European examples can one point to of slaves be promoted up to Admiral level functions, or even governors of important provinces. This seems to be a fairly common phenomena with the Ottomans. It seems from the profiles that a modicum of military or other expertise was sufficient in Ottoman service to get one promoted, whereas Christian Europe seems generally dominated by an attachment to blood nobility.

This, basically. Europeans “turned Turk” because they could. Ottoman & North African societies were very open to military “slaves” rising into social, military and economic power - the Janissary system of recruitment more or less guaranteed it.

Europe had nothing similar. Muslim slaves could not become European generals and admirals.

Eventually, as Europeans became famous (or infamous) for their military skills, you find the same thing happening all over the place - particularly in India and SE Asia, where European adventurers teaching “modern” infantry tactics rise in power in local societies.