You 've merrily mixed up so many issues. Muslims are not ancient but recent or medieval (perhaps for an American anything beyond three hundred years is ancient). Bathing customs in Middle East remain in tact.No point in mixing up the European hygiene with it.
Being far more colder, Europe always had a non-bathing culture (one might catch cold & pneumonia). The great Mathematician Srinivasa Ramanujam of South India, a daily ritualistic bather continued it in England (he must have seen snow for the first time in life there) & died of pneumonia at the age of 36 which was a great loss to Mathematics. Europe has an annual bath as the norm.
I quote this from the words of Chief Vitalstatistix, the Armorican Gaulish (Asterix series) chief. He sat in a tub while his wife Impedimenta, was pouring hot water in his tub, when there was a knock on the door & Roman legionaries appear. The chief says "every time I take a bath the Roman legionaries come knocking on the door.
It happened the last year too". Asterix series is historically authentic It is only after establishment of USA(where Latitudes are more to the south than in Europe) with its not-so-cold climate, bathing daily became necessary, as most of them were engaged in farming etc. The black slaves (being denizens of hot climate) too were responsible. Lastly I might as well tell you that Christianity was an Asiatic religion in form & content that is thoroughly Europeanised by their founding fathers, Peter & Paul.
Now it has nothing Asiatic even about it. So don't mix up the Canaanite customs or attribute them to Scandinavians or Patagonians because of Christian connection. The ubiquitous clothes-lines after daily laundry & home-made soap were customs that began by the offspring of pilgrim fathers, but not in Europe.
For most people in 18 /19th century there was no running water and tiny houses. A bath meant a galvanised tub in front of the ifre I the living room while the dozen children were sent outside to play. In ancient tines only the very wealthy had daily baths.
Normal people had bad teeth, fleas, lice, dist etc.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.