The king [Chlothar]1 had seven sons by several wives; namely, by Ingund, Gunthar, Childeric, Charibert, Gunthram, Sigibert, and a daughter Chlodoswintha; by Aregund, sister of Ingund, Chilperic; and by Chunsina he had Chramn. I will tell you why it was he married his wife’s sister. While he was married to Ingund and loved her alone, he received a suggestion from her saying: “My lord has done with his slave-girl what he pleased and has admitted me to his bed. Now let my lord the king hear what his handmaiden would suggest to make his favour complete. I beg that you consent to find a husband for my sister, your servant, a man of dignity and wealth, so that I shall not be humiliated but rather exalted and shall be able to serve you more faithfully.” As soon as he heard this, because he was licentious beyond all measure, he began to love Aregund and went to the estate on which she was living and married her himself. Having done this he returned to Ingund and said: “I have accomplished the favour which your sweet self asked of me. I looked for a man of riches and wisdom to unite to your sister. I found no one better than myself. And so allow me to tell you that I have married her, which I think will not displease you.” And she replied; “Let my Lord do what seems good in his eyes; only let his handmaid live in favour with the king.”

Gregory of Tours, History of the Franks, 4. 3

Translation based on Earnest Brehaut [1916]

1 c. 497 – 29 November 561, King of the Franks