Do you mean when cars were first out? None. There was barely rules of the road and few cars. In Europe there were licences as early as 1880, but none list the legal driving age.
The legal driving age for montana is 14.5/15 years old
The legal age for driving in Liechtenstein is 18.
The legal driving age in Portugal is 18yrs.
5
16+
18
18
16
16
The legal driving age in Louisiana is 16 years old. However, individuals can obtain a learner's permit at age 15.
They shouldn't until they are of the legal age and a mature age to start driving
The legal driving age in Cyprus is 18. See link below.