North or South American blanket

[Erato]

I'd say North American but certainly not Illinois.  The blanket weavers were in the southwest and Mexico.

[goingloco]

I think this may remain a mystery!  Definitely not Argentina or Illinois, but somewhere in between!

I will try the 2 museums suggested and post an update of any results.

Thank you both for your interest and help.

[Lisa in California]

Like Erato, my guess would be southwest.  The “diamond” is intriguing.

I am very interested to see what the museum staff believe.

[Margow]

I understand that some may see resemblances here to southwestern weaving (e.g. Navajo) and indeed southwestern weavers did incorporate motifs from other areas (e.g. Mexico) in their rugs and blankets.  However, in my view, this particular blanket is typically Central American and probably Mexican.  The central diamond motif is also typical.  In some areas a slit may be woven or inserted into the diamond for the wearer's head to go through, so that the blanket may be worn as a poncho.

When folded up, such blankets are relatively light and portable.  They were (and are) popular tourist souvenirs.  While this blanket may have originated in Central America, the OP's great uncles could well have picked it up elsewhere.

Margow

[goingloco]

I know nothing about the great uncles, apart from what I have gleaned through my tree research.  They may well have travelled, for business or pleasure.  There were World Fairs in Chicago in 1893 & 1933, maybe purchased there by Illinois great uncle?  From 1930 onwards he was living in Canton, Illinois. Not too far from Chicago.  I have 2 other items with a Chicago provenance, so maybe he was a occasional visitor.

I think I can conclude that its not south American, but which great uncle might have sent it will remain a mystery.

Thank you all for the information.