Here you can see the flags of different nations, with a bit of explanation about the flags.
The flower shape in the corner symbolises Altharia's national flower, called the goldstar. Originally, the flag was all black, with a large goldstar in the centre. This flag was in use for more than 600 years. When Altharia became a republic, a red stripe was added to the flag and the flower was decreased in size and moved to the upper left corner.
The Arjan flag is a relatively simple one compared to those of most other NSC nations, but the colours are symbolic: black stands for the tough past, red for the heartache of the present and white for the hope of a better future.
Giggshood flag is quite easy to understand. The G stands for Giggs and H stands for Hood. The first and still running president is named Giggs so thats where the name origins from. The 3 stars symbols the 3 big mountains in Giggshood that runs like a stripe across the country just like on the flag.
The Instirian flag is very symbolical. The five-branches flower is the national symbol of Instir. The three horizontal lanes indicate the conquering tribes. The colour of the flower and the lanes is blue, what indicate the coast of the Sea, and the Ocean, and Instir's two rivers: Muksti and Priksti.
This flag is the result of the fusion between NSC-nations Brugia and Maccha-Bently. The rainbow stripe and the 2 apples refer to Maccha-Bently's previous flag, and the red background and the white crosses refer to Brugia's former flag.
Uniteria is the current flag of Spila. It was adopted on June 10th, 2007, following the enlargement of the Spilian territory. The flag is a tricolor (red, blue and yellow) with a black pattern in the middle in shape of the country's borders. The country had two different flags before, which can be seen on the Spilian Wiki page.
Surstrumpebrogen was adopted as Ugaly's official flag at the same time as the nation's creation. The origins of the flag colors are pretty unclear, but it's rumored that the stripes are a pattern from the favorite pair of socks of the nation's founder, Doo E. Fuel, with the green waves symbolizing foot sweat.