Kicker being, with the advent of the newer form of trench warfare, the huge need of handguns on all sides became rapidly apparent. I don't think there has ever been a war where handguns were used as much as WWI.

The French went to Spain to produce a huge number (maybe over a million) of the .32 ACP "Ruby" pistol. Quality on these ranged from decent to awful, with a lot more awful than good ones. Short lifespan, poor metallurgy and a lack of interchangeability, but the French needed pistols RIGHT NOW, and Spain provided.

What would become Star also sold a much better .32 auto to France.

But more to the point, France also bought smaller numbers of Spanish made Smith Hand Ejector copies chambered in the French 8mm revolver cartridge. These were referred to as the Modele 92 Espagnole. Oddly enough I've never seen a photo of them in use in WWI, but I have seen photos of Vichy police with them in WWII.

The Spanish also sold sort of Webley, sort of S&W Model 3 copies in .455 to the British, the same sort of revolver in 10.4 Bodeo to the Italians, Bodeo copies to the Italians, and a proprietary revolver design to Romania.

The K-frame S&W's have been copied by a number of companies around the
world. While I am sure S&W would rather not have that happening, it is a
testimony to the popularity of that frame size.

COPIES OF THE MODEL 10:
Garate Anitua &Cia, Eibar, Spain made copies of the Model 10 in .32-20 from
1930 through 1936.
Trocaola Aranzabal y Cia, Eibar, Spain made copies of the Model 10 in .38
Special in the period between both world wars.
Gabilondo, Eibar, Spain made copies of the Model 10 between 1955 and 1970
in calibers .22 LR, .32 S&W, .32 WCF, and .38 Special. It is said that a few were
also chambered in .357 Magnum.
Copies of Smith & Wesson Model 10 are produced in Israel by Israel Military
Industries (IMI), called Revolver IMI 9mm. It is chambered in the 9x21 mm.
Copies of the Model 10 are made in Brazil by Taurus, called the Model 82.
These are in .38 Special.
There may be others also. I have not done a lot of research to find out. What I
have found simply reinforces what I said at the beginning. This is one popular
sixgun!

THE MODEL 10 HAS BEEN USED BY THESE COUNTRIES:
Canada- Various Police Forces.
China
Costa Rica
France
Hong Kong Police Force
Icelandic Police
Iran
Ireland- Armed units of the Garda Síochána
Israel
Jamaica
Japan - Used in some prefecture police headquarters since late 1940s.
Jordan
Kingdom of Laos
Latvia
Libya
Malaysia
New Zealand
Nicaragua
Norway - standard firearm of Norwegian Police Service from 1981 until about 2007.
Paraguay
Peru
Philippines
Portugal
Saudi Arabia
Singapore Police Force
South Africa
South Vietnam
Vietnam
Thailand
Turkish National Police
United Kingdom - formerly a police-issue weapon
United States- Military and Police Forces, prisons who had armed guards.

PRODUCED IN THESE BARREL LENGTHS:
2"
3"
4"
5"
6"
Some special contract 2.5" barrels were produced also.

PRODUCED IN THESE CALIBERS:
.38 Long Colt
.38 Special
There was a .357 Magnum - a small prototype run of Model 10-6 revolvers in
S&W .357 Magnum caliber was made by S&W prior to bringing out the Model
13.
Also from the late 1940s to early 1960s Smith & Wesson made a variation of the
Model 10 chambered for .38 S&W called the Model 11 in caliber .38/200 (.38
S&W aka 9×20mmR)

After the war they sold dribs and drabs of new .38-200 guns to nations who'd taken a liking to the overbuilt, underpowered-for-the-size revolvers. I suspect these were new frames with leftover WWII barrels and cylinders. Never seen one outside of photos, and apparently these were never advertised.

The unofficial internal designation for these newer production .38-200 K frames was the "Model 11".

The sixgun that we now know as the S&W Model 10 was first introduced in
1899, making it now over 120 years old. Its continuing popularity is a testimony
to the design. While many will downplay the revolver in this age of autoloaders,
the revolver has been and continues to be a great choice. It served many a
military man or law enforcement well for a very long time, and it will still do so
today.

S&W 1st Model Hand Ejector Military & Police

HISTORY, NAMES and DESIGNATIONS
1899 – Introduced in 1899 as the “Hand Ejector”, it was renamed the "S&W
Military and Police" later in 1899 after being adopted by the military.
1902 - Second Model M&P
1905 - M&P Model 1905
1942 to 1944 "Victory Model" (used by Air National Guard tanker crews until 1991 and by
US Navy security personnel until 1995)
S&W Victory Model
1957 S&W changed the designation to “Model 10” and adopted Model numbers
for all their revolvers.

Model 10 changes:
10-1 1959 Heavy barrel introduced
10-2 1961 Change extractor rod thread for standard barrel
10-3 1961 Change extractor rod thread for heavy barrel, change front sight
width from 1/10" to 1/8"
10-4 1962 Eliminate trigger-guard screw on standard barrel frame
10-5 1962 Change sight width from 1/10" to 1/8" on standard barrel
10-6 1962 Eliminate trigger-guard screw on heavy-barrel frame
10-7 1977 Change gas ring from yoke to cylinder for standard barrel
10-8 1977 Change gas ring from yoke to cylinder for heavy barrel

The Model 10 I bought through the Department Of Corrections. We still use it. Bear Hug stocks by Deacon Deason.