Viscount Somerset of Cashel is in Viscount Ireland.
In 1631 Thomas Somerset 1st Viscount Somerset [aged 52] and Eleanor Barry Countess Ormonde and Ossory were married. She by marriage Viscountess Somerset of Cashel. He the son of Edward Somerset 4th Earl of Worcester and Elizabeth Hastings Countess of Worcester. They were fifth cousin once removed.
Thomas Somerset 1st Viscount Somerset was created 1st Viscount Somerset of Cashel.