How did age of adulthood change through history and to which factors was is linked? When did it become 18 years?
The age of adulthood has often changed throughout history and a link can be made between the safety of a society and the length of time that a child gets to remain a child. In earlier and more turbulent periods, individuals would be seen as adults far earlier as their contribution would be needed for the betterment of the society and family. A good indication of coming of age is the ages at which people married. In the Medieval Period, individuals often married between the ages of 16-20 (with some being married as early as 12), and this would signify their transition into adulthood.
Even though these ages may seem young, most couples were not allowed to marry before the age of 21 without parental consent, and would often spend their early years living at home or nearby. In general, the idea of 18 years being the age of adulthood has only arisen in the Modern Period, and it has only increased with the introduction of more structured legislation, such as workers rights, alcohol laws, and marriage consent.