My flag covered my brother's casket when his body was returned from Okinawa, where he was killed in WWII. It is cotton,9'4" by 4'8", with one slight weather stain. What is its value? Would you like a picture?
Hello. My hat's off to your brother and your family for their sacrifice to our country.
The 48 star flag became official on July 4th, 1912 and remained so until July 3rd, 1859. It was therefore our national flag during 3 major wars: WWI (U.S. involvement 1917-18), WWI (U.S. involvement 1941-45) and the Korean War (1950-53). We were highly industrialized by this period of course and commercial flag production was done entirely by machine. The quantity made throughout this 47-year time frame was massive.
Before 1912 there was no official star pattern for the American national flag. In 1912 President Howard Taft passed an executive order that created, for the first time, an official star configuration for flags used by the Department of the Government, which mean military and government use. This consisted of 6 justified rows of 8 stars. Taft's order also dictated such things as the shape of the stars (5-pointed), the shades of red and blue, and the flag's proportions. Flag collectors prefer unusual star patterns and interesting graphics that are not typically seen on 48 stars flags, most all of which conform to Taft's order, are plain and ordinary.
It is for this reason that most 48 star flags are common and thus lack significant value as antiques.
That having been said, there are some 48 star flags that are valuable. These include, for example, flags that have interesting specific history that can be widely appreciated and flags that are highly unusual with interesting graphics, such as circular star patterns, flags with 8-pointed stars, etc.
Your flag does have interesting specific history, but 20th century military casket flags, given to families, have yet to gain interest among collectors. This is partly because they were given to so many people and partly because they are huge and difficult to display.
All of this said, be sure to make a note and sign it, detailing what you know about it and your brother. I suggest that you pass the flag on to a family member who will care for an appreciate it.
Value might be $100 - $250 at auction.