Sorry if this has been done before (I'm new here

) but I began wondering what would happen had Columbus never discovered America, or if he did and never made it back to Spain to tell the tale. I was thinking of a POD and came up with a few:
- Columbus' ships sink due to a freak storm (Either before or after reaching America)
- Columbus reaches America, but he and most of his crew die there (reasons?)
- Columbus never gets the funding he needs for his voyage
- Columbus never even attempts a voyage to America, and the idea stays just that, an idea.
Any comments or ideas? Is this totally unreasonable? My idea is to put off the discovery of America until as late as I can push it. Once again, sorry if this has already been done.