Jacqueline de Montbel d'Entremont (16 February 1541, in a house near the Louvre Palace, Paris - 17 December 1599, whilst imprisoned in the castle at Ivrea) was a French noblewoman. After her first husband's death, she converted to Protestantism and married Gaspard II de Coligny, who was later killed in the St Bartholomew's Day Massacre.
Jacqueline was the only daughter and sole heir of the Montbel d'Entremont family, a family with several fiefdoms in Savoy, Bresse, Bugey and Piedmont. Her mother was lady Béatrix Pacheco d'Ascalana, a young Spanish woman of Portuguese descent. Béatrix's father was Jean, count of Sifuente and duke of Ascalana, who was descended from Juan Pacheco da Silva, a Portuguese page who had gone to serve the prince of the Asturies around 1440, fought with distinction at the battle of Olmedo and was made duke of Ascalana by the king of Castille and Leon. A drawing of Béatrix by Jean Clouet is now at the Musée Condé. She was maid of honour to queen Eleanor of Habsburg (1498-1558), sister of Charles V, Holy Roman Emperor - on the death of Eleanor's first husband Manuel I of Portugal in 1521 she remarried in 1530 to Francis I of France and moved her Spanish courtiers and ladies in waiting into the Louvre Palace - one of them was Béatrix. Louise de Montmorency, countess of Coligny and mother of Gaspard de Coligny was also in the Louvre at around the same time, whilst another of Eleanor's ladies in waiting was Diane de Poitiers.
After the Duchy of Savoy was occupied by French troops in 1536, the lords of Savoy were all invited to the French court. Charles III, Duke of Savoy fell and was forced into exile in Nice, forcing the lords to abandon Turin and go to meet Francis I. One of them was Sébastien, count of Entremont and Montbel, lord of Montellier, Natage and Saint-Maurice. In Paris he met Béatrix and married her on 17 September 1539 in the presence of the Dauphin (the future Henry II of France), Jean de Menthon, Philibert de Gilly and Louise de Montmorency, wife of Gaspard I de Coligny. Their only daughter and heir Jacqueline was born in Paris on 16 February 1541 and grew up in the Louvre until she was six.