Hiya and Welcome to Rootschat....I don`t know whether you are aware but Daingean was formerly known as Phillipstown named after Mary Tudors husband - Phillip of Spain , so when you are researching any Harte from Daingean , you may have to look for Phillipstown as well in your research...on
www.familysearch.org if you put in Harte in the surname and Ireland in the country box and nothing else , there are over 1000 entries...the earliest HARTE I could find for Daingean or Phillipstown was ROSE HARTE, Phillipstown 1710..she married Andre Labat....I would think there are earlier, but I have only glanced at the pages,,,,you will need to trawl through them slowly to find your Harte in Daingean / Phillipstown......good luck....allan
here is a link explaining Daingean / Phillipstown
http://en.wikipedia.org/wiki/Daingean 