Complex sentence: Among his uncles was Daniel Charles, Count O'Connell, an officer in the Irish Brigades of the French Army, a famous aunt was Eibhlín Dubh Ní Chonaill while Sir James O'Connell, 1st Baronet, was his younger brother.
Split into simpler sentences: Among his uncles was Daniel Charles, Count O'Connell, an officer in the Irish Brigades of the French Army. A famous aunt was Eibhlín Dubh Ní Chonaill, while Sir James O'Connell, 1st Baronet, was his younger brother.