[1] On 14 February 1588 Herbert wrote to Francis Walsingham that he desired to show posterity his affection for his God and his prince 'by a volume of my writing,' by 'a colony of my planting,' and by 'a college of my erecting.'
A vigorous colonist, he recommended that Desmond and Kerry should be combined into a single county; that the government should be wholly in English hands; that Limerick should be garrisoned and fortified, and that an army formed of Monmouthshire men should be maintained to resist foreign invasion.
With the Dean of Ardagh, whom he describes as inclined to papistry, he held many conferences, directing his attention to passages in Augustine of Hippo and John Chrysostom, and to works by Whittaker and Sadaell.
After nearly two years' residence at Castleisland, he acted as vice-president of Munster, in the temporary absence of Sir Thomas Norris, and sat on many commissions to settle disputes but Herbert's work was severely attacked by Sir Edward Denny, high sheriff of Kerry, and owner of Tralee and the neighbourhood, who complained of Herbert's self-conceit, and declared that his constables were rogues, and that the native Irish under his care were ruthlessly pillaged.
Adam Loftus, the lord chancellor, and Sir Warham St. Leger wrote in similar terms, and emphasised Herbert's success as a Protestant missionary.
He married early in life Florence or Florentia, daughter of William Morgan of Llantarnam, Monmouthshire, and left an only child, Mary, who was born about 1578.
He settled by will, dated 12 April 1587, all his property, which included, besides St. Julians and his Irish estates, land in Anglesey and Carnarvonshire, upon his daughter, on condition that she married 'one of the surname of Herbert.'