The American army never wore one during the Indian Wars.
During World War I, the Sam Browne Belt was approved by General Pershing, commander of the AEF, for wear by American officers as a rank distinction.
However, the Army as a whole did not immediately approve its use...
MPs were positioned at stateside docks who confiscated them from returning officers.
The United States Army mandated the Sam Browne belt for overseas soldiers in 1918 under the name "Liberty belt"] and for all service members in 1921, this time under the internationally accepted name "Sam Browne belt".
It was a standard part of the uniform between World War I and World War II.
It was limited in use in 1940 when the Army abandoned sabers and replaced with a cloth waistbelt that was sewn to the officer's jacket.
During World War I, the Marines adopted a brown leather Sam Browne Belt. It was later changed to black, the official color of Navy and Marine Corps leather gear.
It is worn as part of the dress uniform by sword-bearing commissioned officers and enlisted non-commissioned officers (minus the shoulder strap) in the Corps today.
Post-WWI, the Sam Browne belt became ubiquitous amongst American police forces and can still be seen in use by them.
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