Didn't want to clog up the other thread:
This is beginning to veer quite some way from the original topic of this thread but I wonder if there is any relationship between these pea coats and the duffle coat. It's possible the duffle coat evolved from the pea coat.
Both are of military origin I believe. I would guess that the Pea coat preceded the Duffle.
The duffle coat owes its popularity to the British Royal Navy, who issued a camel-coloured variant of it as an item of warm clothing during World War I. The design of the coat was modified slightly and widely issued during World War II. Field Marshal Montgomery was a famous wearer of the coat, as a means of identifying himself with his troops. Large stocks of post-war military surplus coats available at reasonable prices to the general public meant that these coats became a ubiquitous and popular item of clothing in the 1950s and 1960s. The British firm Gloverall purchased surplus military supply of coats after World War II and in 1954 started producing their own version of the duffle coat and continue to do so today. Another Navy design coat that gained popularity among the general public is the Pea coat.