 Osbert was first mentioned in the historical record between 1121 and 1128 when he appears in a charter , which although likely a forgery , probably contains an authentic witness list . This document lists him as " Osbert archdeacon " , which means that he probably held the archdeaconry of Richmond . He was the nephew of Thurstan , who was Archbishop of York from 1114 to 1140 . Presumably he owed his position as archdeacon to his uncle and was probably appointed at a young age . A charter of Thurstan 's , dating to around 1138 , names Osbert explicitly as Thurstan 's nephew . 
 Osbert was first mentioned in the historical record between 1121 and 1128 when he <a href='uninflect' title='1'><mark>appears</mark></a> in a charter , which although likely a forgery , probably <a href='uninflect' title='2'><mark>contains</mark></a> an authentic witness list . This document <a href='uninflect' title='3'><mark>lists</mark></a> him as " Osbert archdeacon " , which <a href='uninflect' title='4'><mark>means</mark></a> that he probably held the archdeaconry of Richmond . He was the nephew of Thurstan , <a href='null_relcl' title='5'><mark>who</mark></a>was Archbishop of York from 1114 to 1140 . Presumably he owed his position as archdeacon to his uncle and was probably appointed at a young age . A charter of Thurstan <a href='null_genetive' title='6'><mark>'s</mark></a>, dating to around 1138 , names Osbert explicitly as Thurstan <a href='null_genetive' title='7'><mark>'s</mark></a>nephew . 
Osbert was first mentioned in da historical record between 1121 and 1128 when he appear in a charter , which although likely a forgery , prob contain an authentic witness list . This document list him as " Osbert archdeacon " , which mean that he probably held tdaarchdeaconry of Richmond . He was the nephew of Thurstan , was Archbishop of York from 1114 to 1140 . Presumably he owed his position as archdeacon to his uncle and was probdeffointed at a young age . A charter of Thurstan  , dating to around 1138 , names Osbert explicitly as Thurstan  nephew .