By the terms of the offer, he would be able to pass the Scottish crown to his descendants by a wife other than Mary.
The Crown of Scotland was to be sent to France, where it was supposed to be kept at the Abbey of Saint Denis.
However, the offer was never realised, as the Hamilton family, who were close to the throne, joined the Protestants and opposed it.
[1] Mary's second husband, Henry Stuart, Lord Darnley, also demanded the Crown Matrimonial.
They agreed that Henry, as the new sovereign, would pardon all the exiled Protestants and allow them to return to Scotland.