John FitzGerald, 1st Baron Desmond

John FitzGerald
Died	August 1261 Callan, modern Kilgarvan
Title	Baron Desmond
Tenure	1259-1261
Nationality	English-Hiberno-Norman
Wars and battles	Battle of Callann
Predecessor	New creation
Successor	Thomas FitzMaurice FitzGerald
Issue	Maurice FitzJohn FitzGerald
Parents	Thomas FitzMaurice FitzGerald Sadbh

John FitzThomas FitzGerald, 1st Baron Desmond (died 1261) was the grandson of Maurice FitzGerald, Lord of Lanstephan. He was the founder of the Desmond line of the FitzGerald dynasty and ancestor of the powerful Earls of Desmond (now extinct), as well as other dynasties, including the modern Green Knights of Kerry and former Black Knights of Glin. The other extinct Desmond Geraldines are the Lords of Decies and the White Knights.

He and his son Maurice son of John perished at the Battle of Callann in 1261, fighting against Fínghin Mac Carthaigh, King of Desmond.

John son of Thomas was succeeded by his grandson, Maurice's son Thomas FitzGerald, 2nd Baron Desmond.

The FitzMaurice Barons and later Earls of Kerry continue in the male line with the current Petty-FitzMaurice Marquesses of Lansdowne, but they descend from the 1st Baron Desmond's nephew, Thomas FitzMaurice, 1st Baron of Kerry, son of his brother Maurice son of Thomas. Thus in fact they represent a "sister" branch to the FitzGeralds of Desmond. However this technically makes them slightly closer to the FitzGeralds of Desmond than either are to the Offaly-Kildare-Leinster Geraldines, represented by the modern Dukes of Leinster, who descend from Gerald FitzMaurice, 1st Lord of Offaly, uncle of the 1st Baron Desmond.

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