Short answers, pulled from the story.
Robert Southey is best remembered for the poem "After Blenheim" and for writing the original version of what became "Goldilocks and the Three Bears," first published in 1837 in his collection The Doctor. He also served as Poet Laureate of Britain from 1813 until his death in 1843.
Byron attacked Southey in the ironic dedication to Don Juan partly because he believed Southey had spread rumours about Byron and Percy Bysshe Shelley being in a "League of Incest" during their time on Lake Geneva in 1816. Byron also held Southey in low literary regard and saw his turn to conservatism as hypocrisy.
Robert Southey was appointed Poet Laureate in 1813, a post he held until his death on the 21st of March 1843. He came to dislike the role, which required him to produce celebratory verse and exposed him to accusations of sycophancy.
As a young man, Southey was a supporter of the French Revolution and co-wrote The Fall of Robespierre with Samuel Taylor Coleridge in 1794. That same year, he and Coleridge discussed founding an idealistic community called a "pantisocracy" on the banks of the Susquehanna River in America.
Southey and Coleridge were close collaborators and became brothers-in-law: Southey married Edith Fricker in 1795 and Coleridge married her sister Sara. Their literary partnership included the joint composition of The Fall of Robespierre in 1794, and Southey was notably generous to Coleridge's abandoned family.
Robert Southey was buried in the churchyard of Crosthwaite Church in Keswick, where he had worshipped for forty years. His friend William Wordsworth wrote the epitaph on the memorial to him inside the church.