The Palace of Ajuda is a neoclassical monument in the civil parish of Ajuda in the city of Lisbon, central Portugal. Built on the site of a temporary wooden building constructed to house the royal family after the 1755 earthquake and tsunami, it was originally begun by architect Manuel Caetano de Sousa, who planned a late Baroque-Rococo building. Later, it was entrusted to José da Costa e Silva and Francisco Xavier Fabri, who planned a magnificent building in the modern neoclassical style.

The 1755 Lisbon earthquake, also known as the Great Lisbon earthquake, impacted Portugal, the Iberian Peninsula, and Northwest Africa on the morning of Saturday, 1 November, Feast of All Saints, at around 09:40 local time. In combination with subsequent fires and a tsunami, the earthquake almost completely destroyed Lisbon and adjoining areas. Seismologists estimate the Lisbon earthquake had a magnitude of 7.7 or greater on the moment magnitude scale, with its epicenter in the Atlantic Ocean about 200 km west-southwest of Cape St. Vincent, a cape in Algarve region, and about 290 km southwest of Lisbon.