Diogo de Boitaca

was an influential architect and engineer of some of the most important Portuguese buildings, working in Portugal in the first half of the 16th century.

His family name occurs for the first time in 1498 in a document of king Manuel I, who granted him an annual allowance for his work at the Monastery of Jesus of Setúbal.

His first name is only mentioned once : in 1515 on the list of the members of the ill-fated expedition to São João da Mamora (present-day Mehdya in Morocco) where the Portuguese lost 4,000 men.

He laid the foundations for this three-aisled hall church with five bays under a single vault, a clearly marked but only slightly projecting transept and a raised choir.

Diogo Boitac was also responsible for the first floor of the vast square cloister with its Manueline decorations.

He built the groin vaults with wide arches and windows with tracery resting on delicate mullions.

He erected the pillars of the Imperfect Chapels, decorated with Manueline motives carved in stone.

In 1510, he was knighted by the Count Vasco Menezes Coutinho for his participation in the ill-fated second siege of Arzila (the present-day Asilah, Morocco) in 1509, after it had been recaptured by the Moors in 1508.

He built the fortress of Mamora (the present-day Mehedia or Mâmora, close to Rabat) that was lost to the Moors in 1515 to become a site for the dreaded Barbary corsairs.