The right of wardship and marriage usually go together, but they were in fact separate rights. An example of them being divided is Thomas Despenser (later Earl of Gloucester.) His mother had his wardship but his marriage was granted to Edmund of Langley who used it for the benefit of his daughter.
The feudal lord was entitled to hold the right of wardship and marriage during the nonage of the heir. So if you were, for example, a feudal tenant of the Earl of Warwick, and underage, he would be entitled to your wardship and marriage. The only overriding rule was that if you held a single square foot of land ‘in chief’ – that is directly from the King – your wardship and marriage went to the King, even if you had twenty manors as the feudal tenant of someone else.
By the fourteenth century, most of the aspects of feudal tenure had been replaced by money rent. No one really wanted knight-service or castle guard anymore. The King’s coins were much to be preferred. However, wardship and marriage continued in the same old way, right up to King Charles I and the Long Parliament, when they were finally, rightly, abolished along with most other feudal relics.
The age of attaining your majority varied. If you were male, it was reached at twenty-one for this purpose. if female, at fourteen if you were married and at sixteen if you were not. (Another incentive to marry your daughters off while they were young.) Until you came of age, your guardian could manage your lands as if they were his own, and take the profits. In theory, he was not supposed to ‘waste’ your lands, that is debase their capital value by such measures as cutting down all your woods and selling the timber, but not all guardians were scrupulous. Some took their ward for every penny, and it was a lucky ward who received her/his inheritance in perfect order with cash in the bank. (It will be noted that these ages did not align with the age of consent for marriage, which was 14 for a male and 12 for a female.)
The King did not necessarily keep wardship in his own hands. In fact, almost invariably he granted or sold them to someone else as part of his overall patronage. Usually, the guardian paid a fixed ‘farm’ at the Exchequer and pocketed what was left. Sometimes the King might tell him (or her) to pay part of the farm to so-and-so. It was a convenient way to fund annuities. Occasionally, mothers were granted the wardship of their sons, but this was a particular favour and not an entitlement. More usually it would be given to some influential individual or, if the wardship was particularly lucrative, to a small group of such persons.
Naturally, people sought to avoid wardship if they could. One way was to arrange a trust (an enfeoffment to use to be precise.) This granted all or part of your lands to a group of trustees who would then follow your instructions. For example, they might pay for your tomb or chantry chapel. Since the trust never died, its lands never fell into wardship. Eventually, the heir would be given control. Another less complicated way was simply to ‘lie low and say nuffin’. hoping that your feudal superior would not note that the right was being evaded. Needless to say, such evasions were often detected.
The right of marriage could also be lucrative. If, for example, you had a daughter but could not afford to dower her adequately, the right to marry her to an heir saved you that dowry. Indeed, you could marry the heir to anyone you liked and pocket all or part of any dowry involved. An heiress could also be married to any one of your choice including yourself or your son. Or you could literally sell her to a third party, as Joan Mohun sold her relation, Matilda Burhersh to John of Gaunt so she could be married to Thomas Chaucer, Gaunt’s client. What you were not supposed to do was marry them to a person of low birth, or who was significantly below them in rank.
In theory, this right of marriage could be bought out, and very occasionally it was. An example I know is the Earl of Southampton in the days of Elizabeth I. However, the cost was the equivalent of several years’ income from the ward’s estate. It was not a cheap option, even if it could be exercised.