The title "To the Ephesians" is found in the Muratorian canon, in Irenaeus, Tertullian and Clement of Alexandria, as well as in all the earliest MSS.
It purports to be by Paul, and was held to be his by Marcion and in the Muratorian canon, and by Irenaeus, Tertullian and Clement of Alexandria, all writing at the end of the 2nd century.
Such an epistle is mentioned in the Muratorian canon.
The brevity of the note and its lack of doctrinal significance prevented it from gaining frequent quotation in the early Christian literature, but it appears in Marcion's canon as well as in the Muratorian, whilst Tertullian mentions, and Origen expressly quotes it.
This is the period indicated by the evidence of the Muratorian Canon, which assigns it to the brother of Pius, Roman bishop c. 1 391 54.