Born in Rio de Janeiro as the eldest daughter of Emperor Pedro II of Brazil and Empress Teresa Cristina, she was a member of the Brazilian branch of the House of Braganza (Portuguese: Bragança).

Her gender, strong Catholic faith, and marriage to a foreigner were seen as impediments against her, and the emancipation of the slaves generated dislike among powerful planters.

[7] She was a member of the Brazilian branch of the House of Braganza through her father, and from birth was referred to using the honorific Dona (English: Dame or Lady).

She and her sister "grew up in a stable, secure environment dramatically different from the one her father and aunts had known, and light years away from the childhood chaos of Pedro I.

After learning of the death of his son Pedro in 1850, he wrote: "This has been the most fatal blow that I could receive, and certainly I would not have survived were it not that I still have a wife and two children whom I must educate so that they can assure the happiness of the country in which they were born.

"[21][22][23] Seven years later, in 1857, when it was more than clear that no more children would be born, the Emperor wrote: "As to their education, I will only say that the character of both the princesses ought to be shaped as suits Ladies who, it may be, will have to direct the constitutional government of an Empire such as Brazil".

[22][24] Although the Emperor still had a legal successor in his beloved daughter Isabel, the male-dominated society of the time left him little hope that a woman could rule Brazil.

[...] In consequence, although he valued D. Isabel as his daughter, he simply could not accept or perceive her in cold reality as his successor or regard her as a viable ruler.

"Pedro II believed, as did most men of his day", says Barman, "that a single woman could not manage life's problem on her own, even if she possessed the powers and authority of an empress.

[27][22][28] As the Portuguese (and later Brazilian) court tradition demanded, the heir of the throne was supposed to have an aio (supervisor, tutor or governess) in charge of his education once he achieved the age of seven.

A way of preparing her for a role as future Empress "would have been to give her from an early age personal experience of the tasks she would face and to relate it to what she learned in the classroom.

[57] The sole male child who was part of Isabel's all female group was Dominique, the only son of the Countess of Barral, who was regarded by the Princess Imperial and her sister as "the younger brother they never had".

[61] Her father sought a match among the royal house of France, and initially Pierre, Duke of Penthièvre, the son of the Prince of Joinville, was considered.

[63] Instead, Joinville suggested his nephews, Gaston, Count of Eu, and Prince Ludwig August of Saxe-Coburg and Gotha as suitable choices for the imperial princesses.

[67] Although Gaston encouraged his wife to read broadly, and the Emperor took her on tours of government offices, her outlook remained one of narrow domesticity.

In early 1871, they were in Vienna, where her sister Leopoldina fell fatally ill and died, leaving Isabel the sole surviving child of her parents.

Despite Isabel's pleas to remain in Europe until after the birth, the Emperor insisted she returned to Brazil so that the child, who might inherit the throne, would not be born abroad.

[82] A doctor and midwife from France were brought over for the birth, to the dismay of local physicians whose pride was wounded by Isabel's use of foreign practitioners.

[84] The Emperor embarked on a major tour of North America, Europe and the Middle East in March 1876, and Isabel was again made regent.

[85] Elections later in the year returned the incumbent government (led by the Duke of Caxias) but fraud and violence during the campaign damaged both its and Isabel's reputations.

[91] Throughout the middle of 1877, during a serious drought in northeastern Brazil that threatened public order, Isabel largely remained at home resting because she was again going through a difficult pregnancy.

[94] Three months later, Gaston, Isabel and their two sons left Brazil for an extended stay in Europe, where Pedro was to receive medical treatment for his arm.

[96] Pedro's treatment proved futile, and the couple made plans to return after the birth (with the assistance of forceps) of their final child and third son, Antônio, in August 1881.

[99] Abolitionism in Brazil was growing in strength, but the government of Conservative João Maurício Wanderley, Baron of Cotegipe, attempted to slow the pace of reform.

[101] After the Rio Police's mishandling of a pro-abolition demonstration in early 1888, Isabel acted and appointed Conservative João Alfredo Correia de Oliveira in Cotegipe's place.

[124] In early 1890, Isabel and Gaston moved into a private villa, which was far cheaper than the hotel, but their father refused to accompany them and remained at the Beau Séjour.

[130] In 1905, Gaston purchased the château d'Eu in Normandy, the former home of King Louis Philippe I, and the couple furnished it with items received from Brazil in the early 1890s.

Their consent was only forthcoming when their second son, Luiz, who had travelled to Brazil but had been forbidden to land by the authorities, married Princess Maria di Grazia of Bourbon-Two Sicilies and Pedro renounced his claim to the Brazilian throne in favor of his brother.

[137] Historian Roderick J. Barman wrote that "in the view of posterity, [Isabel] acted decisively only once on a single issue: the immediate abolition of slavery".

Isabel herself wrote, on the day after the republican coup d'état that deposed her father, "If abolition is the cause for this, I don't regret it; I consider it worth losing the throne for.