In the pre-Islamic Middle East, veiling was the sign of a 'respectable' or married woman, and non-veiling indicated enslaved status.
Joanne, this concept is verified by one of the most respected tafsir writer, ibn Kathir. His commentary on ayah 33:59 -
O Prophet! Tell your wives and your daughters and the women of the believers to draw their cloaks (veils) all over their bodies (i.e.screen themselves completely except the eyes or one eye to see the way). That will be better, that they should be known (as free respectable women) so as not to be annoyed.
Tafsir by ibn Kathir:
Here Allah tells His Messenger to command the believing women, especially his wives and daughters, because of their position of honor, to draw their Jilbabs over their bodies, so that they will be distinct in their appearance from the women of the Jahiliyyah and from
slave women. The Jilbab is a Rida', worn over the Khimar. This was the view of Ibn Mas'ud, 'Ubaydah, Qatadah, Al-Hasan Al-Basri, Sa'id bin Jubayr, Ibrahim An-Nakha'i, 'Ata' Al-Khurasani and others. It is like the Izar used today. Al-Jawhari said: "The Jilbab is the outer wrapper. 'Ali bin Abi Talhah reported that Ibn 'Abbas said that Allah commanded the believing women, when they went out of their houses for some need, to cover their faces from above their heads with the Jilbab, leaving only one eye showing. Muhammad bin Sirin said, "I asked 'Ubaydah As-Salmani about the Ayah: (to draw their Jalabib over their bodies.) He covered his face and head, with just his left eye showing.'" (That will be better that they should be known so as not to be annoyed.) means, if they do that,
it will be known that they are free, and that they are not servants or whores. The above explanation of ibn Kathir means:
Muslim women must always keep their bodies covered whenever they venture out.
Infidel women who do not hide their bodies inside Jilbab and Hijab are either slaves, maidservants or whores.