KeithHarwood

Throughout most of history girls have been considered adult enough to marry at age twelve, boys somewhat older. By Victorian times girls had moved up to 16 and men, although considered adult as about 18ish, weren't considered marriagable until their 50's, when they had established themselves and their household. The shift to 21 seems to be a 20th Century phenomenom and now in most countries has shifted to 18.

On the other hand we have, from a very good authority, that in Japan ladies do not reach the age of discretion until they are fifty. The years from seventeen to forty-nine are considered years of indiscretion.