The 13th New Jersey Regiment Age Analysis
The 13th New Jersey was a Union Civil War regiment organized during July and August 1862. Ten companies averaging about 90 men each were formed with recruits from all over northern New Jersey. The majority came from Newark, Paterson, Jersey City, and Bloomfield.
As per Federal law, soldiers had to be between 18 and 45 to join, though in a typical regiment a few were younger (such as musicians) and a few older (such as officers). But the age rule was rarely followed. Many mid-teen boys and even older men wanting to join up simply lied about their age. Long before photo IDs and even birth certificates became commonplace, a soldier presenting himself to enlist during the Civil War simply stated his age. Even if a recruit looked younger than 18 or older than 45, the recruiting officer most likely overlooked this in order to fill his rolls as quickly as possible.
A careful analysis using census files, birth indexes, and other sources has quantified these incidents in the 13th New Jersey. Some men could not be found in any sources because they used aliases to join, or they had a very common name so it was difficult to pinpoint the correct man who joined. In these cases the reported ages were assumed to be correct. But for the remaining men it could be verified that about 15 percent put down a different age on their form than their true age.
The chart above shows the reported ages of recruits (in blue) plotted with the actual ages (in red). Notice the actual numbers under 18 compared to the reported numbers. On the other hand, the number of those reported as 18 far exceeded the actual number.
On the other end of the chart, a significant number of recruits were older than (some much older) than age upper age limit of 45.
The box plots above help visualize the distribution of reported ages of recruits by company. In a distribution, the first quartile falls below the box, half are within box range (2nd and 3rd quartile groups), and the fourth quartile is above the box. The median age is the solid line, but the average age is also shown.
These help visualize the distribution of reported ages by company. The shorter boxes (such as Company's B, D, F, and K) means most soldiers are closer in age to each other than taller boxes (Company's C, E, G and H).
Note, however that nearly the entire distribution for all companies are between 18 and 45.
The box plots for the actual ages are much different however. While the boxes themselves (2nd and 3rd quartiles) are generally similar, as are the median and average ages, the age distributions are much taller due to younger and older men lying about their ages to join the 13th.