 In 1052 , Domnall 's aforesaid grandfather conquered the Kingdom of Dublin from Echmarcach mac Ragnaill , King of Dublin and the Isles ( died 1064 / 1065 ) , and soon after appointed Murchad as King of Dublin . About a decade later , Murchad appears to have driven Echmarcach from Mann , after which he gained the kingship of the Isles . Diarmait 's deep @-@ rooted authority in Norse @-@ Gaelic Dublin lasted for two decades , and was a remarkable achievement that no other Irish king had ever accomplished . Unfortunately for the Uí Chennselaig , two of Diarmait 's sons — Murchad and Glún Iairn — unexpectedly predeceased their father in 1070 , and Diarmait himself fell in battle two years later . 
 In 1052 , Domnall <a href='null_genetive' title='1'><mark>'s</mark></a>aforesaid grandfather conquered the Kingdom of Dublin from Echmarcach mac Ragnaill , King of Dublin and the Isles (<a href='been_done' title='2'><mark></mark></a> died 1064 / 1065 ) , and soon after appointed Murchad as King of Dublin . About a decade later , Murchad <a href='uninflect' title='3'><mark>appears</mark></a> to <a href='been_done' title='4'><mark>have</mark></a> driven Echmarcach from Mann , after which he gained the kingship of the Isles . Diarmait <a href='null_genetive' title='5'><mark>'s</mark></a>deep @-@ rooted authority in Norse @-@ Gaelic Dublin lasted for two decades , and was a remarkable achievement <a href='null_relcl' title='6'><mark>that</mark></a>no other Irish king <a href='been_done' title='7'><mark>had</mark></a> ever accomplished . Unfortunately for the Uí Chennselaig , two of Diarmait <a href='null_genetive' title='8'><mark>'s</mark></a>sons — Murchad and Glún Iairn — unexpectedly predeceased their father in 1070 , and Diarmait himself fell in battle two years later . 
In 1052 , Domnall  aforesaid grandfather conquered the Kingdom of Dublin from Echmarcach mac Ragnaill , King of Dublin and the Isles ( done died 1064 / 1065 ) , and soon after appointed Murchad as King of Dublin . About a decade later , Murchad appear to done driven Echmarcach from Mann , after which he gained da kingship of the Isles . Diarmait  deep @-@ rooted authority in Norse @-@ Gaelic Dublin lasted for two decades , and was a remarkable achievement no other Irish king done ever accomplished . Unfortunately for the Uí Chennselaig , two of Diarmait  sons — Murchad and Glún Iairn — unexpectedly predeceased their father in 1070 , and Diarmait himself fell in battle two years later .