This letter promoting Citizens National Bank's Christmas Banking Club isn't dated, but I'd guess it's before World War II. Why? Take a look at the logo for Citizens National Bank...that black triangle with a swastika in the middle.
According to Wikipedia: "The symbol has a long history in Europe reaching back to antiquity. In modern times, following a brief surge of popularity as a good luck symbol in Western culture, a swastika was adopted as a symbol of the Nazi Party of Germany in 1920, who used the swastika as a symbol of the Aryan race. After Adolf Hitler came to power in 1933, a right-facing 45° rotated swastika was incorporated into the flag of the Nazi Party, which was made the state flag of Germany during the Nazi era."
The swastika on Citizens National is not the rotated swastika of the Nazi party, but I would doubt the bank retained it for long after the swastika became associated with America's enemies in World War II.
Here's a photo of Citizens National Bank in Raleigh taken in 1914, from http://commons.wikimedia.org/wiki/File:Citizens_National_Bank_Raleigh.jpg:
