Subjectivity encompasses a broad scope and is defined as:
belonging to the thinking subject rather than to the object
pertaining to or characteristic of an individual; personal
placing excessive emphasis on one's own moods, attitudes, opinions, etc (Dictionary.com)
The story of subjectivity in English poetry between 1780 and 1970 is a long and twisting one. Around 1780, poets like Thomas Gray and Robert Burns reacted against the Augustinian period typified by Dryden and Samuel Johnson in which the Roman and Greek ideals were emulated, especially as exemplified during the time of Caesar Augustus. Gray and Burns introduced an emphasis upon the poet's subjective sentiments and feelings.
This new subjectivity led to the Romantic period's deep expressiveness of the poet's subjective experience and feelings as was exemplified by Wordsworth and Coleridge along with others like Shelly and Byron. Milton replaced the Roman and Greek ideals as the source of inspiration. This newly developing subjectivity was carried through to and accelerated by Victorian poets like Robert and Elizabeth Browning. Robert Browning illustrates the deepened subjectivity in dramatic monologues like "Porphyria's Lover." This trend toward the subjective took deepest root during the 1890s in the work of the Pre-Raphaelites and the decadent poets, when fin-de-siecle depended upon the French symbolism model.
Georgian poets reacted against the decadent movement and turned toward sentimentalism, which is a different form of subjectivism, as was seen earlier in Gray and Burns. Robert Graves and D. H. Lawrence are two such Georgian poets. Another branch of poetry during this period is represented by such as Kipling and Henley. Their poems, with subjective sentimental elements, inspired people during the World War I era. Kipling wrote of traditional British virtue, like stoicism, in "If," while Henley wrote of the unconquerable soul in "Invictus." Modernism followed.
From here, the story of subjectivity becomes more complicated and twisting, as everything became more complicated and twisting following two world wars. Modernism, with its fragmented subjectivity best exemplified by Eliot, led to the highly personal, therefore subjective, political criticisms of poets like W. H. Auden. These were followed by New Romantic poets like Dylan Thomas who, in reaction against an earlier emphasis on French classicism by New Country poets, wrote highly personal subjective poems like "Do Not Go Gentle into That Good Night."
Poets like Philip Larkin followed. They wrote from an extreme dislike of modernism and used Hardy's earlier subjectivism as a model. After this, poetry embraced new expressions in performance poetry, sound poetry, and concrete poetry. Their subjective expressions often turned to protests against the social order and nuclear threat. Once subjectivity entered poetry as a reaction against Johnson's and Dryden's Roman Classicism, it never left; it deepened in nature until the present era.