Hi there, I was trying to ID the glass as well. The cutting is very similar to a glass German stein I had a while ago. I thought they were sunflowers, but could be wrong. Test the glass under a blacklight, if it turns green it is a good indicator that it is American. It would not be a minty green, but an apple green. If it just turns bluish it is most likely 20th Century. I have also found that 18th & 19th C. English-Irish glass turns lighter green, such as minty green. Blacklight testing is not 100% by any means, but it is a good test if your stumped. I have also found that German glass has a yellow tint when exposed to natural sunlight on a bright day. It is also typical of German glass to have a thick heavy base to compensate for the lightness of the composition of the glass itself. I checked in a few of my books about it being American, but found no match. Although, I just scratched the surface really. The cutting looks like it could be American, but the base is not as typical. Usually American glasses have a star cut base, yours has a sort of flower cut base. So, all that being said, I might be totally wrong, but thought it might help.
PS~I was able to find a similar cutting on Sinclaire Glass pieces and Tuthill pieces, just not with that shield motif.