By the time of his father's death in 1433, Afonso had won favour with his brother, King Duarte I and the rest of high Portuguese society.

Afonso's elevation to the dukedom, the highest level of nobility, marked the foundation of the House of Braganza, which was to become a key family in Portuguese history.

In 1451, the Count of Ourém was made Marquis of Valença and escorted Infanta Leonor of Portugal to her husband Frederick III, Holy Roman Emperor.

However, Fernando I became a favourite of both the royal and imperial government and of King Afonso V, earning him the position of Governor of Ceuta and the titles of Marquis of Vila Viçosa and Count of Neiva.

Fernando I's children, by his wife, Joana de Castro, Lady of Cadaval, continued to enlarge the influence of the House of Braganza.

Of his nine children, all six who survived to adulthood established themselves either through positions or marriages, though the actions of King João II would seek to weaken their influence.

[12] To the Duke and the House's downfall, however, King João II's reign concerned itself with the royal consolidation of power and the diminishment of the nobility.

[18] Due to their father's misfortunes, Fernando II's children, from his marriage to Isabel of Viseu, daughter of Infante Fernando, Duke of Viseu and Beja, initially had a tumultuous childhood; but King João II's successor, King Manuel I, who had previously himself been the Duke of Beja, chose to forgive the House and re-grant them all their properties in exchange for their loyalty.

Fernando II's oldest surviving son and successor, Jaime I, returned to Portugal and reestablished himself at Vila Viçosa,[18] the former seat of the Dukes.

Fernando II's only other surviving son, Dinis of Braganza, married Beatriz de Castro Osório, Countess of Lemos, and had four children with her.

Jaime I's first daughter, Isabel of Braganza, married Infante Duarte, Duke of Guimarães, and had three children, while his first son and successor, Teodósio I, was a successful prince of the Portuguese Renaissance.

Having been married to Infanta Catarina, daughter of Infante Duarte, Duke of Guimarães, and thus a grandchild of King Manuel I, during the succession crisis of 1580, the couple pressed their claims to the Portuguese throne.

Though Infanta Catarina was a popular claimant, her Habsburg cousin was eventually crowned Philip I of Portugal and the Iberian Union was established.

The Duke's oldest son and successor, Teodósio II, famously fought in the Battle of Alcácer Quibir at the age of ten and later became an accomplished general.

The Duke's support and service to the Philippine Dynasty, earned the Braganzas more lands and titles and, by 1640, the House had amassed around 80,000 vassals, alongside numerous churches, orders, and institutions under its patronage.

Teodósio II's second son, Duarte of Braganza, was made Lord of Vila do Conde and became a diplomat, serving at the court of Ferdinand III, Holy Roman Emperor, but later died a prisoner as a cost of the Restoration War.

Legend says that his wife, Dona Luisa de Guzmán, daughter of the duke of Medina-Sidonia, urged him to accept the offer, saying "I'd rather be queen for one day than duchess for a lifetime."

In 1825, signing the treaty of Rio de Janeiro of this date, his father, King Dom João VI, recognized the independence of the new state, the former Portuguese dominion, now Empire of Brazil.

Unable to deal with the problems in both Brazil and Portugal simultaneously, the Emperor abdicated on behalf of his son, Pedro II, on 7 April 1831 and immediately sailed for Europe to restore his daughter to her throne.

The power vacuum resulting from the absence of a ruling monarch as the ultimate arbiter in political disputes led to regional civil wars between local factions.

Having inherited an empire on the verge of disintegration, Pedro II, once he was declared of age in 1840, at 14 years old, managed to bring peace and stability to the country, which eventually became an emerging international power.

Even though the last four decades of Pedro II's reign were marked by continuous internal peace and economic prosperity, he had no desire to see the monarchy survive beyond his lifetime and made no effort to maintain support for the institution.

Although there was no desire among the majority of Brazilians to change the country's form of government, republicans began pressuring army officers to overthrow the monarchy.

Although there was significant monarchist reaction after the fall of the Empire,[citation needed] this was thoroughly suppressed, and neither Pedro II nor his daughter and heiress supported a forced restoration.

[36] Despite the tradition of following the custom of patrilineal descent of royal houses, common throughout Europe, Article 5 of the Portuguese constitution of 1826 stated that "The Reigning Dynasty of the Most Serene House of Braganza Shall Continue in the Person of Lady Princess Maria da Glória, by the Abdication and Cession of Her August Father Lord Pedro I, Emperor of Brazil, Legitimate Heir and Successor of Lord João VI.".

Maria Pia of Saxe-Coburg and Braganza, who claimed she was an illegitimate daughter of King Carlos I of Portugal, began asserting that she was the heir to the throne from 1957.

After the end of World War II, Prince Pedro Henrique, then Head of the Imperial House and married to Princess Maria Elisabeth of Bavaria, returned to Brazil with his family.

The Imperial House of Brazil divided into rival branches because of the renunciation of Pedro de Alcântara, Prince of Grão-Pará in 1908 and the subsequent repudiation of that act by his descendants.

[53] Members of both the so-called Petropolis branch of Braganzas (Princes Pedro Gastão and his nephew, Joazinho of Orléans-Braganza) and the more broadly recognised Vassouras line of the Imperial Family led by Prince Luiz Gastão of Orléans-Braganza, participated in the restoration effort,[52] and the Head of the Vassouras branch continues to lead a movement to restore the monarchy.

For supposedly mistreating a Franciscan friar, a curse was purportedly placed on King João IV of Portugal, stating that never again would a first-born male of the Braganza Dynasty live long enough to succeed to the throne.