- Not to be confused with Cardinal Niccolò Albergati-Ludovisi
He was the son of Orazio Ludovisi, patrician of Bologna and commander-in-chief of the Papal Army (as well as brother of Pope Gregory XV), and Lavinia Albergati. He was the nephew of later-Cardinal Niccolò Albergati-Ludovisi. He was a brother of Ludovico Ludovisi who was made a cardinal by their uncle the pope.
Ludovisi was married three times. After a first marriage (30 November 1622) with Isabella Gesualdo, princess of Venosa, in 1632 Niccolò married Polissena Appiani, the daughter and heiress of Isabella Appiani, Princess of Piombino.
Niccolo Ludovisi had seven children:
- with his first wife Isabella Gesualdo (1611–1629):
- Lavinia (1627–1634), died in childhood
- with his second wife Polissena Appiani (?-1642):
- Gregorio Filippo (1633-c.1637), died in childhood
- with his third wife Costanza Pamphili (1627–1665):
- Giovan Battista (1647–1699), Prince of Piombino from 1664
- Olimpia (1656–1700), Princess of Piombino (1700), unmarried
- Lavinia (1659–1682), married Giangirolamo, Duke of Atri but had no issue
- Ippolita (1663–1733), Princess of Piombino (1700–1733), married Gregorio II Boncompagni and had issue
- Niccolo (c.1664-1665), died in infancy
- Jaitner, p. 167
- Ludwig von Pastor, History of the Popes, vol. 27, London 1938, p. 66.
- The Scented Salamander: Prince Niccolò I Ludovisi
Klaus Jaitner, Die Hauptinstruktionen Gregors XV.: Für die Nuntien und Gesandten an den europäischen Fürstenhöfen, 1621-1623, Bibliothek des Deutsches Historisches Institut in Rom, Max Niemeyer Verlag, 1997, pp. 167–178. ISBN 3-484-80146-8, ISBN 978-3-484-80146-2
To the Holy Roman Emperor
| Prince of Piombino
Giovan Battista Ludovisi