 Edwin died in battle at Hatfield fighting against Penda of Mercia and Caedwalla in 633 . Edwin had been the main supporter of Paulinus ' mission , and with his death , a pagan backlash set in . Paulinus fled to Kent , along with Æthelburg and Edwin and Æthelburg 's daughter Eanflæd . James , however , remained behind in Northumbria and continued missionary efforts . James ' efforts were centred in Lincoln , at a church that Paulinus had built there , the remains of which may lie under the church of St. Paul @-@ in @-@ the @-@ Bail . This was in the dependent kingdom of Lindsey , where Paulinus had preached prior to Edwin 's death , and it was reconquered by one of Edwin 's successors , Oswald of Northumbria in the 640s . 
