In the Medieval Times, with parental permission it was legal for boys to marry at 14 and girls at 12.
A betrothal often took place when the prospective bride and groom were as young as 7 years old and in the case of higher nobility many were betrothed as babies. But a marriage was only legal once the marriage had been consummated.
(According to the book Marriage in Medieval Times By Rachelle Carter)
Until perhaps the 1200s it was common to marry earlier than now. For example, age 12 (and even younger) was quite common for girls. Nowadays, it would be assumed that they should be at high school or college at that age.
For girls in particular the age of marriage was much closer than now to the onset of fertility. In the 1600s the minimum legal age for marriage in England was 12. Parliament raised the minimum age for marriage (and the age of consent) to 16 in 1885
The above is just 200 years ago. Now compare it to the reality of 1200 years earlier! (with reference to 1885)
The age of consent in one of the American States was just 7 years, just 120 years ago! But the Western people did not know that and just criticized Islam and Muslims for the marriage of the Mohammed and Aisha more than 1400 years ago.
Traditionally, the age at which individuals could come together in a sexual union was something either for the family to decide or a matter of tribal custom. Probably in most cases this coincided with the onset of MENARCHE in girls and the appearance of pubic hair in boys, that is, between 12 and 14, but the boundaries remained fluid.
[b]In the Semitic tradition,[/b] betrothal could take place earlier than PUBERTY, perhaps as early as 7-9 years, but the marriage was not supposed to be consummated until the girl menstruated and was of age. This is analogous to what is obtainable in most part of Africa
[b]In medieval Europe[/b], Gratian, the influential founder of Canon law in the twelfth century, accepted the traditional age of puberty for marriage (between 12 and 14) but he also said consent was "meaningful" if the children were older than seven. Some authorities said consent could take place earlier. It was this policy which was carried over into English common law. Similarly Gratian's ideas about age became part of European civil law.
Though Shakespeare set his Romeo and Juliet in Verona, the fact that Juliet was 13 probably reflects the reality in England. Her mother, who was 26 calls her almost an old maid.
The American colonies followed the English. For example in Virginia in 1689, Mary Hathaway was only 9 when she was married to William Williams.
Judges honored marriages based on mutual consent at age younger than 7, and there are recorded marriages of 2 and 3 year olds. The 17th-century lawyer Henry Swinburne distinguished between the marriages of those under seven and those between seven and puberty. He wrote that those under seven who had said their vows had to ratify it afterwards by giving kisses and embraces, by lying together, by exchanging gifts or tokens, or by calling each other husband or wife. A contemporary, Philip Stubbes, wrote that in sixteenth-century East Anglia, infants still in swaddling clothes were married. The most influential legal text of the seventeenth century in England, that of Sir Edward Coke, made it clear that the marriage of girls under 12 was normal, and the age at which a girl who was a wife was eligible for a dower from her husband's estate was 9 even though her husband be only 4 years old.
In England for example in the parish of Middlesex County, Virginia, there is a record of 14-year-old Sarah Halfhide marrying 21-year-old Richard Perrot. Of the 98 girls on the 10-year register, three probably married at age 8, one at 12, one at 13, and two at 14.