"George" refers to George Stanley, a poet whom Spicer had known since 1956, when Stanley was invited to join a poetry workshop that Spicer was conducting in San Franciso: "George Stanley's relation to Spicer was problematic from the beginning, perhaps because the two were very alike -- voluble, argumentative, and passionate about poetry" (Ellingham and Killian 83). Ellingham and Killian report that "the differences between Spicer and Stanley sometimes grew into an active hostility -- nasty banter publicly, ungenerous comments privately" (215). They go on to say that

Jack's ongoing, passive-agressive hostility toward Stanley received indirect acknowledgment in Spicer's writing of 1962-64. For example, The Holy Grail [...] contains the lines, "George / Said to me that the only thing he thought was important in chess was the killing of the other king. I had accused him of a lack of imagination."
From Poet Be Like God: Jack Spicer and the San Francisco Renaissance by Lewis Ellingham and Kevin Killian.