Complex sentence: Archbishop Donatus O'Murray was a fifteenth century Archbishop of Tuam, an archdiocese in western Ireland surrounding Galway, who granted the status of collegiate church to the St. Nicholas' Collegiate Church in Galway in 1484.
Split into simpler sentences: Archbishop Donatus O'Murray was a fifteenth century Archbishop of Tuam, an archdiocese in western Ireland surrounding Galway. He is notable for having granted the status of collegiate church to the St. Nicholas' Collegiate Church in Galway in 1484.