John Fitzgerald, 1st Baron Desmond

John Fitz-Thomas inherited the title of Lord Conello from his father. He became the founder of the Desmond line of the Fitzgerald clan and the ancestor of the Earl of Desmond (now extinct), as well as other clans, including the modern Green Knights of Kerry and the extinct lines of the Black Knights of Clay , the Lords of Desise and the White Knights .

In 1259, John Fitzgerald received a royal letter to the feuds of Desmond and West Waterford . Fingen McCarthy , son of Donal Gott McCarthy and the Irish King Desmond (1251–1261), gathered an army to confront the English protege. On the McCarthy side were also the O'Sullivan and O'Donoghue clans .

In August 1261, at the Battle of Callan, three Irish clans of McCarthy, O'Sullivan and O'Donoghue defeated the army of John Fitzgerald, Baron Desmond. John Fitz-Thomas Fitzgerald himself and his son, Maurice Fitz-John Fitzgerald, died in this battle.

After the death of John Fitzgerald, the baronial title was inherited by his grandson, Thomas Fitz-Maurice Fitzgerald, 2nd Baron Desmond (d. 1298 ).

The Barons of Fitzmoris, later Earls of Kerry, descend on the male line from the Petty-Fitzmoris family , the Marquis of Lansdowne , who descend from Thomas Fitzmoris, 1st Baron Kerry (d. 1260 ), the nephew of 1st Baron Desmond and the son of his brother Maurice Fitz Thomas Fitzgerald. Thus, the counts of Kerry are a kindred line of counts of Desmond from the Fitzgerald dynasty. They are related by the Dukes of Leinster , who are descended from Gerald Fitz-Maurice, 1st Lord Offaly , Uncle John Fitzgerald, 1st Baron Desmond.

John Fitzgerald had a son, Maurice Fitz-John Fitzgerald , who died with his father at the Battle of Callan. The baronial title was inherited by Thomas Fitzgerald, 2nd Baron Desmond, John's grandson and Maurice's son.

• Curtis, Edmund. A History of Ireland , Routledge, 2005, ISBN 9781134466665 , p. 75
• Webb, Alfred. A Compendium of Irish Biography . Dublin: 1878.
• "The Battle of Callann, AD 1261"