SOME OF YOU WILL SALUTE THESE FLAGS; SOME OF YOU WON'T. . HOW MANY CAN YOU IDENTIFY?

Pinpointing the origin of flags is not that clear cut as use in Rome is obvious, but before that, China, and before that, Egypt, all documented.  

The Nordic word is fla.ka, meaning "to flap, to flutter."  Sure, the discovery of silk around 2700 B.C.E. factors, but not before the use of wool and cotton in 6000 B.C.E.

Some flags off the top of my head: