The Bowl on Yam was done in uhh 1964?  And it is 10a (the crux pitch done onsight, in boots, on zero gear, hardman stuff, etc).  Surely there were other routes near that grade at the time.

The upper pitch of the left side of Yosemite Pinnacle on Tantalus Wall, which I’ve done, is an offwidth/squeeze chimney in the mid 5.10 range. It was done free in 1965, led by Hamish Mutch. It’s hard to grade squeeze chimneys and offwidths, but it’s very doubtful it’s easier than 5.10.

Another ‘route’ from that period that may be 5.10 is the direct variation on the third/fourth pitch of Slab Alley. Just above the three-bolt ladder, at the ledge, you move left and mantle into the bottom of the solution groove. I’m not sure when it was done.

I’ve also heard the stories about Les MacDonald doing some sort of free climbing on the second/third pitch of the Grand Wall bolt ladder, sometime in the mid 1960s, but never thought to ask him about it. Maybe I will - it would probably be hard to identify now what he climbed (if anything, apart from a few moves), but anything in that area would be good 5.10 or harder.

We climbers can be a bit parochial about priority, and other things. The first 5.10s, by modern gradings, were probably in the Elbe region of Germany, before World War I. Oscar Eckenstein is the first recorded boulderer - at Pen Y Pass in North Wales, in the 1880s and 1890s. Some cliff dwelling peoples - the Anasazi in the U.S. southwest, the monks on various isolated places, inhabitants of Mali - were doing amazing things on rock long before we decided to make it a game with silly rules.

I believe the first routes graded 5.11 in the U.S. were done in the mid 1960s, but many of them were subsequently altered by piton placements (e.g. Serenity Crack), and so it would be difficult now to determine relative difficulty and such.