Short answers, pulled from the story.
Bacchylides was a Greek lyric poet born around 518 BC on the island of Keos and died around 451 BC. He was the nephew of the poet Simonides and was included in the canonical list of Nine Lyric Poets by later Greeks.
A papyrus containing Bacchylides's poems was found in Egypt, reportedly in a ransacked tomb between the feet of a mummy, and purchased by the Egyptologist Wallis Budge at a price he called preposterous. Budge smuggled it out by concealing it dismembered and disguised as a packet of photographs, escaping via switched trains, covert embarkations, and a midnight rendezvous with a P and O steamship. He presented it to Frederic Kenyon at the British Museum in 1896.
Bacchylides and Pindar were direct rivals who sometimes composed odes for the same patron and the same victory, including Hieron of Syracuse's Olympic win with the racehorse Pherenicus in 476 BC. Pindar is generally regarded as the greater poet, but translator Robert Fagles argued that blaming Bacchylides for not being Pindar is as mistaken as condemning Marvell for missing the grandeur of Milton.
Bacchylides composed in nine genres: hymns, paeans, dithyrambs, processionals, songs for maidens, songs for light dances, songs of praise, victory odes, and songs of love. This was a wider variety than any of the other nine canonical lyric poets except Pindar, who composed in ten genres.
Ode 5 was composed for Hieron of Syracuse to celebrate his Olympic victory with the racehorse Pherenicus in 476 BC. It contains a description of an eagle's flight that one modern scholar called the most impressive passage in Bacchylides's extant poetry, and it allows direct comparison with Pindar's Olympian Ode 1, which celebrates the same victory.
Before the discovery of the Egyptian papyrus in 1896, only sixty-nine fragments totalling 107 lines survived. The papyrus allowed Frederic Kenyon to reassemble 1,382 lines, of which 1,070 were perfect or easily restored, and to publish twenty poems, six of them nearly complete. The papyrus remains in the British Library in a form totalling almost fifteen feet and thirty-nine columns.