Who married Helen Roche?

Donogh O'Brien, 4th Earl of Thomond and Baron Ibrickan, PC (Ire) (died 1624), was a Protestant Irish nobleman and soldier, and Chief of Clan O'Brien. He fought for Queen Elizabeth during Tyrone's Rebellion and participated in the Siege of Kinsale. He obtained the transfer of County Clare, where most of his lands lay, from the Province of Connacht to that of Munster. He was made president of Munster in 1605.