 The date of first construction of a church in Llangaffo ( a village in Anglesey about 5 miles ( 8 @.@ 0 km ) south of the county town of <unk> ) is uncertain . The village takes its name from the church : the Welsh word <unk> originally meant " enclosure " and then " church " , and " <unk> " is a modified form of the saint 's name . St Caffo , a 6th @-@ century Christian , was a companion of St <unk> and was martyred by shepherds in the vicinity of what is now Llangaffo , perhaps in revenge for his brother <unk> insulting <unk> Gwynedd , the local ruler . It is thought that there may have at one point been a monastery in this location , known as " <unk> Caffo " : <unk> is the Welsh word for " martyr " , and in place names means a building erected near a saint 's grave . 
