British poetry is a term rarely used, as almost all poets of the British world (whether of the British Isles, the British Empire, or the United Kingdom) are clearly identified with one of the various nations within those areas.
British poetry is the field of British literature encompassing poetry from anywhere in the British world (whether of the British Isles, the British Empire, or the United Kingdom). The term rarely used, as almost all such poets are clearly identified with one of the various nations or regions within those areas.