The primary account of the martyrdom of Maurice and the Theban legion occurs in a letter addressed by Eucherius, bishop of Lyons c. 434–50, to a fellow bishop, Salvius. This relatively brief document has attracted a degree of scholarly attention out of all proportion to its length, the purpose of which has been to investigate its historical basis. There are those who believe with varying degrees of certainty that there is a historical basis to the story which Eucherius relates, that there did indeed exist a group of Theban soldiers who were executed in the Alps during the early years of the reign of Emperor Herculius Maximianus because they refused, for religious reasons, to obey his commands. However their arguments have left many unconvinced. Denis Van Berchem's thorough examination of the story has raised many doubts about its veracity, and many commentators now incline to believe, with him, that no such martyrs ever existed.