Junia Theodora is not considered to have any connection to the Junia mentioned in the Bible. However, she was a wealthy citizen of Corinth, and a benefactress who also had an inscription of letters in her honour. The Greek text can be read online in the Bulletin de Correspondance Hellenique, 1959.
The Council and people of Myra to the rulers of Corinth, greetings. Many of ours being in your territories testify to Junia Theodora, daughter of Lucius, citizen of yours, for the goodwill and effort that she made on their behalf, occupying herself continually on behalf of ours, at the time of their arrival in your city. According her our approval for her goodwill to the city, we hold her in the greatest esteem, and have decided to write to you in order that you may know of the gratitude of the city.
This inscription was not discovered until 1954 and contains five letters of recommendation for Junia Theodora, who, according to St. Paul’s Corinth: Text and Archaeology was a native of Lycia, a citizen of the city of Corinth and a Roman citizen. She aided the Lycians financially, with hospitality and with influence on the authorities of Corinth. This inscription has brought awareness that Junia (IOUNIA in Greek) was the name of a well-known woman of Corinth, and that this woman was an important patron of her people. The Greek word προστασια was used in reference to the support which she offered the Lycians travelling to Corinth. This is related to the word used to refer to Phoebe in Romans 16 – προστατις. The Lycian Federation sent her a gold crown in recognition of her deeds.