Scriptor Incertus de Leone Armenio ("unknown writer on Leo the Armenian") is the conventional Latin designation given to the anonymous author of a 9th-century Byzantine historical work, of which only two fragments survive.
2014 manuscript (interposed into descriptions of the Avaro-Persian siege of Constantinople and the Second Arab Siege of Constantinople, as well as hagiographical texts) in the Vatican Library, deals with the 811 campaign of Emperor Nikephoros I (r. 802–811) against the Bulgars, which ended in the disastrous Battle of Pliska.
[1] The date of authorship is disputed, but the vividness of the narrative suggests that it was written by a contemporary of the events described.
[1] The two fragments were identified[4] as forming part of the same work by Henri Grégoire based on similarities in style.
[1] Both fragments provide information not included in the contemporary histories of Theophanes the Confessor and Theophanes Continuatus, and Grégoire hypothesized, again based on style, that the Scriptor Incertus was a continuation of the work of the 6th-century historian John Malalas.