All German, that is, they all come from molds made by German firms, originally, for homecasters.
The field piece looks like a Schneider, the Roman is by a company called Ideal ("Ee-day-all", in German, but it means the same thing).
The knight may also be by Ideal, too. They had a good number of Ancients and Medieval Knights in their catalog. He's missing the top of his head, though. There should be a plume atop his helmet.
The field piece looks like a short-shot, that the melted metal did not fill the mold completely.
They all look like homecasts of a poorer quality, with a relatively higher lead content, making for a soft casting, with soft details.
As to age, very difficult to tell, because the molds exist and so many people have them. Also, depending on the alloy used, and how they were kept (in a box in a garage, in the flowerbeds, etc), two figures from the same batch could look very different, after a time.
If you paint, I recommend painting them up and having fun.
Thanks for sharing your find with us, prost!
Brad