Peter Jones and I -- don't ask me why -- just spent a half hour trying to remember every significant act who recorded on Capitol in the 50s. Here's our list, and this is all off the top of our heads -- Googling occasionally to verify, but no Google-fishing.
birth of the cool
the five keys
Jackie Gleason - which was Bobby Hackett
Duke Ellington (at least one album)
Tennessee Ernie Ford
There must be a use for this knowledge.