This country is divided into 48 ceremonial counties, some are large, others not so. Some are very heavily populated, others more sparsely. Although all under the United Kingdom, and thus the Union Flag, each county has developed its own flag and it is on these that this puzzle is based.
N54 AB.CDE W001 FG.HJK
A = Three white flowers on a green background, above water.
BC = A rampant horse on a red background.
D =Paly of eight Or and Gules per fess embattled all counterchanged
E =St Petroc's cross
FG = Green background, with an historical mythical figure connected to the county.
H = vertical bi-colour of gold and black, with a white bend bearing nine black ermine spots alternating between pairs and singles.
JK = The three gold crowns represent East Anglia, with wavy light blue lines representing a local river, in the colours of a local University on a dark blue background.
Once the counties have been identified, you will need to decide how they can be put into some order, to create the required numbers.
+++ Be careful, some lists are different to others ... +++
(With thanks to Kixy52 for pointing out my errors.)