The Cosmopolitan Club was dedicated to inter-faith and inter-racial understanding. In my view the Club took an interest in learning about global cultures that was notable for its time. Events included an annual Japanese dinner with a discussion of Japanese culture; Rabbis and Christian religious leaders discussing faith; an annual Heroes of Peace event memorialized deceased members of the community by recognizing groups such as firefighters, mothers and soldiers.
You might like to take a look at the collection's finding aid: http://eadsrv.denverlibrary.org/sdx/pl/toc.xsp?id=WH1270&qid=sdx_q5&fmt=...
for more details about the Club.
I suspect the club may not have outlived Clarence Holmes, but the collection shows Club items that span 1931-1970s. The Club minutes book is a wonderful source of information about the clubs' activities and discussions.