Labraid Loingseach was great grandson of Ugaine Mor (Ugaine the great) and grandson of Loguire Lorc who were both also High Kings of Ireland.
LEBOR GABALA ERENN records Ugaine as being High King of Ireland, and Britain. After his marriage to the daughter of the Celtic King of France, Ugaine is also reputed to have become king of France and then take the Kingship of all Europe.
"He took the kingship of Ireland and of Alba and to the Sea of Wight and to the Tyrrhene Sea ; and he took Cessair Grothach daughter of the king of France to wife..They took the kingship of all Europe to the Caspian Sea".. "Ptolomaeus Philadelphus became king of the World when Ugoine died."
Alba is Britain.. to the Tyrrhene Sea (would be France down to the Mediterranean) and then to the Caspian - (which is East of Eastern Turkey, north of Iran) - This was the full extents of the Celtic world at that time (300s BC) After Ugaine's death, the Pharoh of Egypt was then said to be the undisputed ruler of the world .. ie Ugaine was a rival, as king of the (then known) world, when Ugaine was alive.
Here is the text:
The Celtic Empire did reach the Black sea and at its height (around this time) was expanding through Turkey towards the Caspian Sea. There also were incursions into Egypt
Here is a view of the extent of their influence:
