The short answer is no, there is no historical evidence that in antiquity all respectable Christian women always covered their heads in public while only prostitutes went without one.
While early Christian writers strongly encouraged or mandated head covering for women as a sign of modesty and submission, the idea that an uncovered head was an exclusive marker of prostitution in the ancient world is largely a modern simplification that doesn't hold up to historical scrutiny of the broader Greco-Roman culture.
Here is a breakdown of the historical reality:
1. The Christian Practice
From the earliest centuries, Christian leaders like Tertullian (c. 155–220 AD), Clement of Alexandria (c. 150–215 AD), and John Chrysostom (c. 347–407 AD) taught that Christian women should cover their heads not only during worship but also in public. They viewed this as a distinct "Christian custom" that set believers apart from the pagan world https://www.bible-researcher.com/headcoverings3.html https://en.wikipedia.org/wiki/Head_covering_for_Christian_women.
* Tertullian argued that virgins, widows, and wives alike must be veiled to show modesty and distinguish themselves from the "shameless" https://www.bible-researcher.com/headcoverings3.html.
* Clement of Alexandria instructed that women should be "entirely covered" when outside the home https://en.wikipedia.org/wiki/Head_covering_for_Christian_women.
The Didascalia Apostolorum* (3rd century) explicitly told Christian women to cover their heads in the marketplace https://emilygossard.substack.com/p/christian-tradition-of-head-coverings.
2. The Reality of Non-Christian Women
The claim that only prostitutes went uncovered is a myth when applied to the general population of the Roman Empire or Greece.
* Greek and Roman Customs: In 1st-century Corinth and Rome, head covering customs were fluid. While respectable women often wore head coverings (like the palla in Rome or himation in Greece), it was not an absolute rule that an uncovered head automatically signaled prostitution. Many respectable women, especially in the upper classes during the 1st and 2nd centuries, appeared in public with their heads uncovered or with elaborate hairstyles that were visible https://en.wikipedia.org/wiki/Head_covering_for_Christian_women https://theancientbridge.com/2015/07/unravelling-headcoverings-the-historical-context-of-first-century-roman-wives-pt-1/?print=print.
* Fashion and Status: In Rome, the wearing of the stola (a specific robe) was the traditional sign of a married woman, but by the 1st century, this custom was already declining, and women of all classes were experimenting with fashion. Tertullian himself complained that in Rome, "no distinction [was] left in dress between matrons and harlots," implying that respectable women were not consistently distinguished by their veils in the way later Christian writers hoped would be the case https://en.wikipedia.org/wiki/Head_covering_for_Christian_women.
* Prostitution Markers: While some ancient laws (like the Middle Assyrian Laws) explicitly forbade prostitutes from covering their heads, and some later Christian writers claimed that uncovered women were prostitutes, archaeological and literary evidence suggests that in the Greco-Roman world, an uncovered head was not a definitive or exclusive marker of prostitution. Many respectable women appeared unveiled in art and literature https://en.wikipedia.org/wiki/Head_covering_for_Christian_women https://www.headcoveringmovement.com/articles/is-head-covering-cultural-what-about-the-corinthian-prostitutes.
3. The Confusion in Corinth
The specific context of 1 Corinthians 11 is complex. Some scholars argue that Paul was addressing a specific local issue in Corinth where some women were removing their head coverings during worship, possibly influenced by pagan mystery cults (where women sometimes worshipped unveiled) or a new "liberated" fashion trend among wealthy women https://en.wikipedia.org/wiki/Head_covering_for_Christian_women https://www.headcoveringmovement.com/articles/is-head-covering-cultural-what-about-the-corinthian-prostitutes.
Some apologists argue that in Corinth specifically*, the custom was strict enough that an unveiled woman might be mistaken for a prostitute, but historians generally agree that the cultural norms were not that binary. The idea that "only prostitutes went uncovered" is often cited in sermons but is not supported by a comprehensive reading of ancient sources https://en.wikipedia.org/wiki/Head_covering_for_Christian_women https://headcoverings.org/book-chapters/chapter04-what-early-christians-believed-about-the-head-covering/.
In fact, some high-class prostitutes (hetairai*) in Greece were known for their elaborate, uncovered hairstyles, but so were many respectable women in certain contexts https://en.wikipedia.org/wiki/Head_covering_for_Christian_women.
Conclusion
While Christian women in antiquity were indeed taught to cover their heads as a sign of their faith and modesty, the strict dichotomy that "Christian women always covered, and only prostitutes didn't" is an oversimplification. Respectable non-Christian women in the Roman Empire frequently appeared unveiled, and the link between an uncovered head and prostitution was not a universal law of antiquity, though it may have been a local perception in certain contexts or a later Christian interpretation used to enforce the practice https://en.wikipedia.org/wiki/Head_covering_for_Christian_women https://www.headcoveringmovement.com/articles/is-head-covering-cultural-what-about-the-corinthian-prostitutes https://headcoverings.org/book-chapters/chapter04-what-early-christians-believed-about-the-head-covering/.