James Conlon at The Hudson Review:
The evolution of Peter Grimes’s character through the course of Britten’s collaboration with Peter Pears, Montagu Slater and Ronald Duncan (the librettist of his subsequent opera The Rape of Lucretia), can be traced, to some degree, from various extant earlier versions of the libretto. Floating in the background of the genesis of Britten’s first great opera were the influences of E. M. Forster (whose article on George Crabbe’s “The Borough” first attracted the attention of Britten and Pears during their stay in southern California), W. H. Auden and Christopher Isherwood. It reveals the gradual transition from the specific homosexual orientation of its protagonist to a broader context.
Consider the following statements: Pears, having heard some of the new score, wrote to Britten, “The more I hear of it, the more I feel the queerness is unimportant and doesn’t really exist in the music (or at any rate obtrude) so it mustn’t do so in words. P.G. is an introspective, an artist, a neurotic, his real problem is expression, self-expression.” This can be compared with Britten’s own statement about the focus of the work: “[A] central feeling for us was that of the individual against the crowd, with ironic overtones for our own [Pears and Britten’s] situation.” Musicologist Philip Brett writes, “The remark was addressed to the social situation in which the two found themselves—pacifism, in this instance as on other occasions in Britten’s life, doing double duty as a controversial but mentionable position for still unspeakable homosexuality.”
more here.