I am trying to find the correct John Mcalpine/John Mcalpin to go back a generation - he married Margaret Donaldson in 1807 and was in the Berwick Militia. His first child George was born in England in 1810 so it is likely he was still in the Militia at that time. After that a shoemaker in Linlithgow.
Can anyone tell me the minimum age, if there was one, that you could join.
All able bodied men between the ages of 18 and 30 were eligible to be balloted to be in the Militia. After 1802, the upper age was raised to 45. If they have several children under 10 years of age, they were also exempted. Do you know where he was living ? If in Berwick, you could try the Northumerland & Durham FHS or the Berwick Record Office as they may have the Militia lists. If he lived in Berwickshire or in the Borders, the hub have a fair number of the militai lists. Borders FHS have been transcibing the lists and including them in the Monumental Inscription publications.