“The Strength of Weak Ties” (1973) by sociologist Mark Granovetter is an extraordinarily influential paper, one of the most cited in sociology (with nearly 30,000 citations, according to Google Scholar). Yet it was initially rejected. You can read the rejection letter via a link from here. It is an interesting case of peer reviewers dismissing an idea because they were apparently distracted by how a familiar term (alienation) was used in an unfamiliar way, and a corresponding lesson for authors about framing. (Thanks to Elizabeth Cohen for bringing this to my attention.)
Are there similar stories in philosophy of now-famous papers first being rejected? Bonus points if you have images of the rejection letters.