Antoninus Pius
Scholars name Antoninus Pius as the leading candidate for an individual identified as a friend of Rabbi Judah the Prince. According to the Talmud (Avodah Zarah 10a–b), Rabbi Judah was very wealthy and greatly revered in Rome. He had a close friendship with "Antoninus", possibly Antoninus Pius, who would consult Rabbi Judah on various worldly and spiritual matters.