Iure uxoris

Jure uxoris is a Latin term that means "by right of (his) wife".Jure is the ablative case of jus, meaning a legal right. It is most commonly used to refer to a title of nobility held by a man because his wife holds it suo jure ("in her own right"). Similarly, the husband of an heiress could become the legal possessor of her lands jure uxoris, "by right of [his] wife", as in England where, until the Married Women's Property Act 1882, married women were legally incapable of owning real estate. Jure uxoris monarchs are not to be confused with kings consort, who were merely consorts of their wives, not co-rulers.

Although the underlying concept can be applied to the nobility of any culture that practices male-preference primogeniture, the term is usually used only in the context of European history.

During the feudal era, the husband's control over his wife's real property, including titles, was substantial. At the point of marriage the husband gained the right to possess his wife's land during the marriage, including any acquired after the marriage. Whilst he did not gain the formal legal title to the lands, he was able to spend the rents and profits of the land and sell his right, even if the wife protested.

Jus uxoris was standard in the Middle Ages even for queens regnant. In the Kingdom of Jerusalem, Fulk, King of Jerusalem, Guy of Lusignan, Conrad of Montferrat, Henry II, Count of Champagne and Amalric II of Jerusalem all received their titles as a result of marriage.

Sigismund of Luxembourg married Queen Mary of Hungary and obtained the crown through her, retaining it after her death. After the death of Sigismund, Albert II of Austria inherited the throne of Hungary by marrying the king's daughter Elizabeth of Luxembourg.

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