Where does the Hijab come from?

What Islamists do not admit is that the custom of the veiling of women in early Islam was not part of the dress code until Muslims conquered Persia and the Byzantine territories in the 7th century. It was only after this assimilation of the conquered cultures that head covering and veiling were viewed as appropriate expressions of Islam practice. Since the veil was impractical attire for working women, a veiled woman was a sign that she belonged to the upper class and that her husband was rich enough to keep her idle.

Chasing the Mirage, by Tarek Fatah, p 291