Actually, that's by Strombecker, part of the series they made of diorama sets. There's also a Yorktown set, with a cannon and Washington touching off the first shot; an Iwo Jima set; and a Civil War set, including a mounted Federal cavalryman. I'd have to look it up, to see if there's a connection between Strombecker and Monogram.
Your set is the "Battle of Liege 1914-German Staff Officers Meeting". I have a couple of those, and I've collected about 8 or 9 of the Yorktown sets, to have a battery of artillery.
The figures were cast in a strange alloy, not white metal, ie, not a tin/lead/antimony alloy, but an alloy containing either zinc, aluminum or magnesium. They have a distinctive feel, light for their size, and they clink when knocked together or tapped with a piece of metal.
They're actually pretty well done, considering when they were produced. Yours look pretty good, Scott!
Prost!
Brad