The palace was first begun by Si Musa, grand vizier under the Alawi sultan Muhammad ibn Abd al-Rahman, in the 1860s.

[1][2] Si Musa was descended from a family of black slaves which served the Moroccan makhzen (royal government) and reached the highest offices in the country.

[5] Ahmad ibn Musa, known also as Ba Ahmed, was hajib to Sultan Moulay Hassan and, upon the latter's death, ensured his son Abdelaziz's accession to the throne in 1894, earning him a promotion to grand vizier.

[7][11] Ba Ahmed was responsible for constructing most of the Bahia Palace's southern parts, which include various smaller courtyards and riad gardens.

[5] On the east side of this palace complex, he created a vast private park and garden, complete with a central water basin.

[5][7] The palace's growth overtook much of the previously existing neighbourhood north of the Mellah and resulted in major changes in the local street layout.

[5] The growing palace housed Ba Ahmed's servants (including his own slaves) and his harem (private family residence).

[6][12] The entire palace was built on one level, possibly as Ba Ahmed's own physique (which was described as stout and obese) made it more difficult for him to go up and down stairs.

Mere hours after his death, Sultan Abdelaziz (who subsequently took full power over the country) reportedly ordered the palace to be looted for valuable items.

[12] Today, the palace is one of the most visited tourist attractions in Morocco; the government counted 410,141 visitors from January to April 2019, more than any other heritage site in the country.

[16][17] The palace's labyrinthine layout, which does not reveal a clear unified plan, is due to the fact that it was expanded in a piecemeal fashion in different stages over many years.

[19] At the east end of this courtyard is a grand hall (known as the Salle d'Honneur in French), measuring 20 by 8 meters and featuring a high ceiling with some of the best painted decoration in the palace.

[6][8] The materials for this decoration were imported by Ba Ahmed from all over Morocco, including marble from Meknes (possibly from former Moroccan royal palaces), cedar wood from the Middle Atlas, and tiles from Tetouan.