It seems that as time went on, the Spaghetti Western became increasingly interested in portraying half breeds in westerns as lonely, laconic, heavenly people. Keoma for example, is crucified and is shown almost like a christ like figure. Why do you think that is? Why did the Italian filmakers use this idea so often? What were there intentions if any?
Navajo Joe is an early example and wasn’t Bill Kiowa from Tommorrow We kill, tommorrow we Die! also a Half Breed? 
Half Breeds are interesting because they live between two different cultures and have to fight for acceptance in both. I would also see movies in which a white kid grows up among indians in that category and became later a SW Hero like Jonathan of the Bears.
It’s no coincidence either that Italians were interested in usingthe Half Breed formula with a number of films about Half breeds:
Navajo Joe
Vengeance
Today We Kill, Tomorrow We Die
Chino
Chato’s Land (yeah yeah I know)
Keoma
Once Upon a Time in the West
Django Kill
Fighting Fists of Shanghai Jo (not a half breed but goes through the same trials)
Jonathan of the bears
Requiescant (kind of)
I recognize no deeper meaning in every SW.
Sometimes its surely only the fact that the most tales took place in a area where different countries and cultures forgathered.
In north america the new arrivals and indians,in the borderland the mexicans and gringos and so on.
A very good example,even a female,is Loredana Nusciak as Maria in Django
Not thought much about half breeds in westerns whether Italian or U.S westerns, just accepted them for what they are.
The very same here
I think that in many cases the halfbreed functioned like the bounty killer - his ambiguous/outcast status vis-a-vis conventional Western archetypes was of great interest to the more ideologically minded/iconoclastic Euro-Western film-makers. He enabled many artists to make their politcal/anti-racist points more forcefully, while even those who weren’t ideologically minded preferred outcasts and mxed-race characters to more straightforward hero figures, often with the same effect. (I’m thinking principally of escapist films such as My Name is Pecos and Vengeance here.)
Of course, a great many films simply followed the lead of the more thoughtful examples.
This can all be taken with a pinch of salt, but I don’t think the large number of halfbreed antiheroes is merely coincidence.
Very true also, and reflected most famously in Clint Eastwood’s mixture of American/Mexican attire in the Dollars movies. When they got it right, the ‘melting-pot’ milieu was one of the Euro-Western’s greatest strengths.
Surely no discussion of the half breed in the european western can be undertaken seriously without reference to the classic example of this type…White Comanche 
Agree,
most of those ‘melting pot’ movies rank among the best