The boy-emperor Leo II has bequeathed us more than his share of chronological puzzles. He was only seven years old when he died in 474 but he had possessed imperial authority for nearly half his short life. There is uncertainty about the date of his birth, and most of his career as emperor with his grandfather Leo I. If we still had the chronicle of Nestorianos which actually terminated at the death of Leo II we would probably be fully informed on these matters. Instead, several of the relevant documents have been consistently misconstrued, that is, they have been made to fit a predetermined interpretation or order of events. Moreover, one important text has been ignored altogether. The chronology of the boy-emperor's career depends on Seeck's Regesten which has inevitably shaped the coverage in the standard accounts of Bury and Stein. The authority of Seeck also underpins the entry in the Prosopography of the Later Roman Empire which sets out the following chronology of Leo's brief life and imperial career: 467 - birth; 473 - elevated to Caesar by Leo I, October; 474 - elevated to Augustus by Leo I, before 18 January; 474 - death, November. This investigation is designed to show that the multiple phases in the imperial rule of Leo II have never been properly disentangled. To do so not only brings greater precision to the sequence of events, and to Leo's short career, but also casts light on the wider context of these turbulent few years.