Aside from Pigafetta's account, Amorsolo is said to have undertaken painstaking historical research that included reading other available 16th-century Spanish accounts on the Philippines, consulting with prominent scholars of the time, namely Trinidad H. Pardo de Tavera and Epifanio de los Santos, and finding visual sources on 16th-century Spanish costumes, arms and armor that would have been worn by Magellan and his men.

More complicated, however, were the costumes of the pre-colonial Filipinos for which there was little or no visual reference in Amorsolo's time. Today, artists are still limited by extant historical accounts of the Philippines and the Filipinos at the point of contact in the 16th century, but there are more archaeological artifacts available for study and reference. Most important is that we now have a visual record of early Philippine costumes, jewelry and weapons as found in the illuminated illustrations for the Boxer Codex, a manuscript on the Filipinos made circa 1590.

Aside from artifacts in the pre-war National Museum and a handful of private collections in Manila, Amorsolo based his costumes and weapons largely on those still in use by thriving cultural communities. A handful of his extant works in pencil and oil comprise visual documentation of Mindanao costumes, particularly those of the Bagobo, known for their colorful and intricate bead work. In reconstructing images of the pre-colonial past, Amorsolo had to supplement the scant historical material at his disposal with his imagination.

Amorsolo was not alone, nor the first in depicting 16th-century Philippines. Aside from Luna, as mentioned in the beginning of this essay, the other 19th-century Filipino master Felix Resurreccion Hidalgo also tried his hand at historical painting, likewise augmenting his narrow knowledge of pre-colonial Philippines with available artifacts and his imagination. Extant photographs of the Paris studios of Luna and Resurreccion Hidalgo reveal that they collected ethnographic objects and other "props" that eventually became small details in their historical paintings. For example, on the wall of Resurreccion Hidalgo's studio hung a Kalinga shield and head axe. In a group photograph taken in the courtyard of the Paris studio of Resurreccion Hidalgo, perhaps in 1889, Rizal is shown playing the flute, wearing a helmet and body armor, probably reproductions of the Spanish type used in the 16th century.

In El pacto de sangre [Blood Compact], a large painting that now hangs in Malacanang, Luna used his friends as live models: Trinidad H. Pardo de Tavera modeled for Legazpi and Rizal for Sikatuna. To depict a proud pre-colonial chief, Luna painted Sikatuna wearing a plumed helmet and the distinctive chain-mail and carabao horn armor known as kurab-a-kulang. Sikatuna also clutches a dagger with a gold handle, his strong muscular arm embellished with tattoo. Hidalgo was less successful in this regard, in one work entitled Tomb of the Chief, pre colonial Filipinos are garbed with feathered headdresses that resemble those worn by American Indians!

Unlike Luna, Amorsolo did not lack live models for his paintings. He even said the sweet faces of some of the women in his historical paintings were based on members of his family. Pre-colonial Filipinos are shown wearing gold jewelry, a fact that was repeatedly mentioned by Pigafetta and other 16th and 17th-century Spanish chronicles. This has also been validated by recent archaeological finds in ancient trading centers like Butuan and Surigao. Obviously, Amorsolo read widely, but was naturally limited by the state of historical research available in his day. For example, the two paintings, Princess Urduja (which depicts a masculine pre-colonial princess and her band of Amazons) and Sale of Panay (which depicts the Bornean datus buying Panay from Negritos for the price of a golden salakot) used to be highlights of pre-colonial history, until they were debunked in the late 1960's as myths. However, it is not fair to judge Amorsolo on the basis of what we know today. While there may be little or no historical basis for Urduja, Kalantiaw, or the Bornean Datus In Panay, these have become an important part of Philippine folklore and deserves continued study.

Despite his care and meticulous research, there were occasional slips. For example, in a painting described as Early Sulu Wedding, there is something quite striking-the bride kneeling in front of an imam is topless except for her garland and gold necklace. Her headdress was inspired by Indonesian rather than Philippine examples. In another canvas depicting the encounter between Miguel Lopez de Legazpi and a chieftain in Manila, one can clearly see two distinct types of shields carried by the warriors. One is a Bagobo shield (from the South) and the other a Kalinga shield (from up North in the Cordilleras), making the props visually interesting but historically unlikely.