uncle uncle

My bicycle knowledge, for what that might entail, doesn't really go back as far as all of the 1960's; it basically starts at the USA bike boom years (starting in the late 60's) and goes from there. I know that enthusiast riding in the USA was much more limited, but I wonder what would have been some of the bicycles one might expect to see in the peleton of a club ride in the pre-boom years? How about over in the UK, France, & Italy (the title wouldn't let me add more words, so I'm adding them here)...? Was there one particular bike that was an overwhelming favorite? Thanks, in advance, for any responses.