Haven't found a good picture of a matching scabbard, however, I think that it may have been a scabbard for a "Knights of the Globe" sword. Here is a picture of the sword and a description of the scabbard design which seems to match:
This is a very unique and beautiful sword and scabbard acquired at an estate auction featuring many WWI and turn of the century items. I have never seen one with a globe pommel before. Research tells me it was made for a member of the Knights of the Globe, a fraternal benefit orginization that began in Chicago in 1889. It was made by C.F. Foster Son and Company. The markings are very interesting. The pommel is engraved with the words PATRIARCHAL CIRCLE. The knuckle guard features two partially drawn swords, one with an eagle head pommel and the other with a dog head pommel. The emblem at the top of the scabbard is of a hand holding a sword in a scabbard. The emblem in the middle of the scabbard shows flames coming from the top of a pillar and two stone tablets representing the ten commandments. The handle is a beautiful swirl of brass and leather. Appears to have been gold plated with normal signs of wear on the scabbard.
Also, look at the sword in the attached picture... The hand guard looks like it somewhat matches up with the design behind the partial globe on your scabbard piece. Although I don't actually see two tablets, I do see a scroll which might have been later/earlier than the one described above.
Hmmm... Fits with Illinois as well....
-whynot