Based on archaeological findings and the earliest written sources, it is believed that Prague Castle was established around 880 AD by Prince Bořivoj of the Přemyslovci dynasty.

The early medieval site was fortified with a moat and a clay-and-stone rampart. The first stone structure was the Church of the Virgin Mary. Additional churches, dedicated to St. George and St. Vitus, were constructed in the first half of the 10th century.

From the 10th century onwards, Prague Castle served as the seat of the ruling princes and later kings, as well as the highest religious authority—the bishop of Prague. The first convent in Bohemia, for Benedictine nuns, was also established on the castle grounds, adjacent to St. George's Church.

The Basilica of St. Vitus, built on the site of the original rotunda, became the primary castle church in the 11th century, housing the relics of saints Vitus, Wenceslas, and Adalbert. In the same century, the Prague convent grew into a significant educational and cultural center.

Under the reign of King and later Emperor Charles IV in the mid-14th century, Prague Castle experienced a period of prosperity. It became the imperial residence and the seat of the Holy Roman Empire. The royal palace was extensively remodeled, fortifications were strengthened, and the Gothic St. Vitus Cathedral, inspired by French cathedrals, began construction.

Building projects continued under Charles's son, Wenceslas IV, but the Hussite Wars and subsequent decades of neglect left the castle in disrepair.

A revival came after 1483, when the new Jagellon dynasty restored the castle as their residence. New fortifications and defense towers were built on the northern side, including the Powder Tower and Daliborka. Architect Benedikt Ried expanded the royal palace, adding the grand Vladislav Hall, which at the time was the largest vaulted hall in Europe and featured early Renaissance architectural elements.

The Habsburg dynasty later transformed Prague Castle into a Renaissance residence. The Royal Garden was established, and entertainment venues like the Summer Palace, Ball Game Hall, and shooting range were constructed. During the 16th century, both the cathedral and royal palace were further modified, and new residences were built along the southern ramparts.

Prague Castle reached its peak under Emperor Rudolph II in the late 16th century. Rudolph made the castle his permanent residence, turning it into an imperial center, and built the northern wing, which includes today's Spanish Hall, to house his extensive art and scientific collections.

The Defenestration of Prague in 1618 sparked a long period of wars, during which the castle was damaged and looted. It was rarely used by the country's rulers during this time.

In the latter half of the 18th century, the last major renovations transformed the castle into a chateau-like residence. However, as Vienna had become the capital of the empire, Prague was relegated to a provincial town, and the castle fell into disrepair, with much of its artistic wealth diminished.

After Emperor Ferdinand V abdicated in 1848, he chose Prague Castle as his residence. The Chapel of the Holy Cross was renovated for the occasion, and the Spanish Hall and Rudolph Gallery were prepared for the coronation of Franz Joseph I, though it never took place.

A movement to complete St. Vitus Cathedral arose, led not by the monarchy but by the patriotic Union for Completing the Cathedral of St. Vitus. The cathedral was finally completed in 1929.

Following the establishment of Czechoslovakia in 1918, Prague Castle once again became the seat of the head of state. Slovene architect Josip Plečnik was commissioned to oversee renovations beginning in 1920.

Today, Prague Castle continues to undergo restoration and improvements, not only for maintenance but to increase public access. Since 1989, previously closed areas, such as the Royal Garden, Ball Game Hall, and Southern Gardens, have been opened to visitors.

Prague Castle remains the official residence of the president and is an important cultural and historical monument. It houses the Czech Crown Jewels, relics of Bohemian kings, valuable Christian artifacts, art treasures, and historical documents. Important national events are still held within its walls, making the castle a living symbol of the Czech Republic's historical legacy.