Andrews, brought the Catholic Church in Scotland into conformity with that of the larger Gaelic world, although it is not known exactly what this means. There had been Gaelic bishops in St. Andrews for two centuries, and Gaelic churchmen were amongst the oldest features of Caledonian Christianity. The reform may have been organizational, or some sort of purge of certain unknown and perhaps disliked legacies of Pictish ecclesiastical tradition. However, other than these factors, it is difficult to appreciate fully the importance of Constantine's reign. Malcolm I to Malcolm II The period between the accession of Malcolm I (Maol Caluim Mac Domhnuill) and Malcolm II (Maol Caluim Mac Cionaodha) is marked by good relations with the Wessex rulers of England, intense internal dynastic disunity and, despite this, relatively successful expansionary policies. Some time after an English invasion of cumbra land (Old English for either Strathclyde or Cumbria or both) by King Edmund of England in 945, the English king handed the province over to king Malcolm I on condition of a permanent alliance. Some time in the reign of King Indulf (Idulb mac Causantín) (954–62), the Scots captured the fortress called oppidum Eden, i.e. almost certainly Edinburgh. It was the first Scottish foothold in Lothian. The Scots had probably had some authority in Strathclyde since the later part of the 9th century, but the kingdom kept its own rulers, and it is not clear that the Scots were always strong enough to enforce their authority. In fact, one of Indulf's successors, Cuilén (Cuilén mac Ilduilbh), died at the hands of the men of Strathclyde, perhaps while trying to enforce his authority. King Kenneth II (Cionaodh Mac Maol Chaluim) (971–95) began his reign by invading Britannia (possibly Strathclyde), perhaps as an early assertion of his authority, and perhaps also as a traditional Gaelic crechríghe (lit. "royal prey"), the rite by which a king secured the success of his reign with an inauguration raid in the territory of a historical enemy. The reign of Malcolm I (942/3–954) also marks the first known tensions between the Scottish kingdom and Moray, the old heartland of the Scoto-Pictish kingdom of Fortriu. The Chronicle of the Kings of Alba reported that King Malcolm "went into Moray and slew Ceallach." The same source tells us that King Malcolm was killed by the Moravians. This is the first definite sign of tension between the Cenél nGabráin and Cenél