The Holy Martyr Hermeningilda, Prince of the Goths in Spain (+ 586), abandoned the Arian heresy and was converted to Orthodoxy. His father, Leovigild, was King of the Goths, and an Arian. Neither by flattery nor by threats was he able to sway his son to return to his former faith. Therefore, Leovigild gave orders to throw him into prison.
On Pascha, as Hermeningilda lay there in his fetters, Leovigild sent an Arian bishop to the prison so that his son might receive the vile communion of the heretics. The king offered to free Hermeningilda and restore him to his former position if he would partake of that communion. The saint, however, drove the Arian bishop away, upbraiding him for his heresy. An Orthodox priest came to the prison secretly and imparted the Life-Giving Mysteries of Christ to St Hermeningilda.
When the Arian bishop reported St Hermeningilda's words to the king, he ordered him to be executed. After he was beheaded, angels were heard singing over his holy relics. The faithful glorified God when they heard of this, and the martyr's father repented of his evil deed.
Although he did not accept Orthodoxy himself, he nonetheless permitted the holy Bishop Leander to convert his successor Rekhardt to the true Faith. After he became king, Rekhardt affirmed Orthodoxy in his domain.
The full account of St Hermeningilda may be found in St Gregory the Great's Dialogues (Book I, Ch. 31).