Thomas the Presbyter (fl. 640) was a Syriac Orthodox priest from Mesopotamia who wrote the Syriac Chronicle of 640, which is also known as the Chronicle of 724 or Book of the Caliphs. The Chronicle of 640 is an idiosyncratic universal history down to the year AD 640. It survives only in a single manuscript codex, now British Library, Add MS 14,643. This manuscript was copied in 724 and the copyist added a single folio of text to the end, containing a list of caliphs translated from Arabic. Although it has been taken as an integral part of the text, the copying scribe clearly marked off his addition by preceding it with the words "it is finished" to indicate the end of the work he was copying.