At an uncertain date he became a monk at St Albans Abbey; afterwards he was appointed prior of the cell of Belvoir, but he forfeited this dignity in the early years of Henry III, having been found guilty of wasting the endowments.
His best-known chronicle, called the Flores Historiarum (Flowers of History), is based in large part on material which already existed at St Albans.
Roger claims in his preface to have selected "from the books of catholic writers worthy of credit, just as flowers of various colours are gathered from various fields."
Begun at St Albans based upon the Chronicle of Matthew Paris, it was finally completed at Westminster continuing to the year 1326.
Roger's work, like that of most chroniclers, is, valued not so much for what he culled from previous writers as for its full and lively narrative of contemporary events, from 1216 to 1235,[1] An example being his description of King John's troops action in the north during the bitter war at the end of his reign: The whole land was covered with these limbs of the devil like locusts, who assembled to blot out every thing from the face of the earth: for, running about with drawn swords and knives, they ransacked towns, houses, cemeteries, and churches, robbing everyone, sparing neither women nor children.