U.S. flag with 39 stars from 1875-1889.
There never was an "official" 39 star U.S. flag. However, flag manufacturers betting on early sales misjudged by believing the two Dakotas would be admitted as one state and the others would be delayed until after the 4th of July. Both Dakotas, Montana and Washington were made into states in November, 1889 and Idaho was admitted July 3, 1890. Any 39 star flags in existence were probably made in the fall of 1889

A noteworthy artifact from the Star Spangled Banner Flag House Collection.