[2] Domingo de Oña was born in Burgos, Spain in 1560 and ordained a priest in the Order of the Blessed Virgin Mary of Mercy.

[3][4] On 27 August 1601, he was appointed during the papacy of Pope Clement VIII as Bishop of Coro.

[2][3][4] On 9 December 1601, he was consecrated bishop by Domenico Ginnasi, Archbishop of Manfredonia.

[3] On 27 June 1605, he was appointed during the papacy of Pope Paul V as Bishop of Gaeta.

[1][3][4] He served as Bishop of Gaeta until his death on 13 October 1626.