Location Sao Paulo Church

A booklet named “Thailand and Portugal: 470 years of friendship” from the Calouste Gulbenkian Foundation (Lisbon, Portugal), created for the Bicentennial celebrations in Bangkok in 1982 CE, became the basis for the Foundation’s involvement in Thai–Portuguese heritage projects and cultural connections. José Martins published "Early Portuguese Accounts of Thailand" in Lisbon in 1983 CE, linking Portuguese historical presence to Ayutthaya.

Archaeological excavations at the São Pedro / St. Dominic (São Pedro) Dominican site in Ayutthaya began in 1984 CE. The project was led by the Fine Arts Department (Archaeology Section / Archaeological Division) of Thailand, in cooperation with the Calouste Gulbenkian Foundation, with support/coordination from the Portuguese embassy under Ambassador José Eduardo de Mello Gouveia.

In 1934 CE, Dr Joaquim de Campos (1893–1945 CE), a Portuguese historian, author, and diplomat who served as the Portuguese Consul in Bangkok (1), surveyed the Portuguese enclave in Ayutthaya. He analysed early Portuguese documents and provided historical context, identifying locations and linking them to current regional knowledge. From the survey, he created a map showing the Christian churches in the Portuguese enclave. The map labels three churches: Igreja S. Domingo (St. Dominic Church), Igreja de S. Francisco (St. Francis Church), and Igreja de S. Paulo (St. Paul Church).

José Gomes Martins, a Portuguese writer and chronicler who has published memoirs and chronicles about Thailand (Memórias de Banguecoque - Memoirs of Bangkok), recounts Portuguese life and impressions in Thailand during the late 20th century. Martins’ work is more personal and anecdotal, highlighting cultural encounters, diplomacy, and the Portuguese community abroad. Based on the annotation on the de Campos map, Martins indicates that he visited the site in 1982 CE, 48 years after de Campos's visit, and observed that "Practically nothing had changed". A picture taken by him in 1994 CE shows the São Paulo Church area, as believed at the time, as the Fine Arts Department maps show.

Excavations by the Fine Arts Department in 2008 CE, in situ, revealed no evidence of a Christian Church. Still, Buddhist artefacts were discovered instead, leading to the conclusion that the site was a temple ruin. The site was named Wat Pho Chai.

The exact location of the São Paulo Church is still unknown today.

The Quest for the Location of the São Paulo Church

In 2010 CE, I tried to locate the church's foundations using old maps that showed its location. To my knowledge, only two maps existed: Simon de La Loubère's map (2) and Jean de Courtaulin de Maguelonne’s (1638-? CE) map.

I used de La Loubère's map to locate the São Paulo Jesuit Church because it has a good bar scale and appears more accurate regarding Ayutthaya Island. But the old French map isn't perfectly oriented or projected. The rivers are stylised and misaligned, and the map has artistic distortions.

Since I didn't have a proper map called “Plan de la Ville de Siam” from the French publication “Du royaume de Siam” (1691 CE), I used “A Map of the Citty of Siam” from the English edition “A new Historical Relation of the Kingdom of Siam”, published by Thomas Horne in London in 1693 CE.

The English edition differs from the French one by omitting the northern part of the original, while the legend labels are in English. Some features might have changed. The map has likely been reduced to save print space, allowing several engravings to be placed on one page for publication. The map shows São Pedro and São Paulo along the riverbank, each surrounded by either a moat or a wall.

Using a transparent overlay of de La Loubère's map, I attempted to find a match. First, I overlaid the north bank of what was then the Lopburi River second, I overlaid the west bank of the same river and finally, I positioned the French and Portuguese churches. All these attempts failed because de La Loubère's map does not match the current aerial view of the terrain. It is largely misaligned and distorted.

Next, I created a smaller overlay that only partially covered the Portuguese settlement, using the São Pedro (San Petro) Church as a reference point. The overlay of the Portuguese settlement provided a general idea of its position, but de La Loubère's map remained disproportionate.

The next step was to use the scale bar indicated on de La Loubère's map. The measurement was in “Toises,” an old French measurement used before 1812 CE, where one toise equalled 6 feet or 1.949 meters.

I printed the map on an A4 sheet. The scale bar indicated 800 toises and measured 5 cm. Therefore, 1 cm equals 160 toises, or 312 meters.

The distance between the central points of the São Pedro and São Paulo churches on the map was 2.75 cm, which equals 858 meters. When measuring the distance on Google Maps, the central point of the São Paulo church was located south of a moat of Khlong Thet, which branched off eastwards into the old Lopburi River.

The distance on the map between the outer moats of the São Pedro and São Paulo churches was 2.2 cm, which equals 686 meters. When measured on Google Maps, the distance was 692 meters.

Although the distance between the south moat of São Pedro and the (probable) north moat of São Paulo seems quite accurate, the central point of São Paulo is about 40-50 meters south of the Khlong Thet moat. I adjusted the central point of the São Paulo Church relative to the Khlong Thet moat and placed it about 50 meters north of the moat (1).

I compared the grounds of São Paulo Church with an aerial map from 1944 CE from the Williams Hunt Collection (WHC). Wat Pho Chai is clearly visible. East of Wat Pho Chai, there is a square formed by the east moat of Wat Pho Chai Rang and two moats running from Khlong Thet toward the old Lopburi River. These two moats are probably the northern and southern moats of Wat Pho Chai. Since the WHC map shows a square formed by moats nearly identical to those on de La Loubère's map, there is a possibility of a match.

Reflections on the Jesuit church

It is a little strange that brickwork from the São Pedro Church was found, yet no remnants of the São Paulo Church, which was also built of stone, were found. The latter was a smaller church, as shown by the pictures on the map of de Maguelonne, yet some brickwork should still be underground, despite de Choisy’s writings on the Jesuit Church.

Abbé de Choisy (1644–1724 CE), in his work “Journal du voyage de Siam fait en 1685 & 1686”, was not too enthusiastic regarding the Portuguese churches: "Two or three leagues below the city, on the riverbank, to the left, there is a small mound which the Siamese call Baan Yesuit, that is to say, the Village of the Jesuits. There, one can still see two stone steps, some bricks, and a stone holy water fountain. A little higher up, there is another similar mound which is called Baan Yacobin, that is to say, the House of the Jacobins." (3)

The Portuguese Padroado system and the French-led Missions Étrangères de Paris (MEP) were frequently at loggerheads, especially in Asia, because both claimed overlapping authority over Catholic missions. Their rivalry reflected a deeper struggle between Portugal’s royal patronage rights and Rome’s Propaganda Fide, which often supported French missionaries. We can expect a French abbot not to write much in favour of their Portuguese neighbours.

The Jesuit mission was still active at the fall of Ayutthaya, as the São Pedro and São Paulo churches were plundered after the French Bishop Pierre Brigot (1713-1791 CE) and his Christians surrendered on 23 March 1767 CE. There must be some traces of the Jesuit Mission's location.

A re-calculation 15 years thereafter

Fifteen years ago, I used the English edition of de La Loubère's map to find the São Paulo Church because I didn’t have a workable French edition at the time. I decided to do the exercise again, this time using the French edition "Du Royaume de Siam" published in 1691 CE at Paris by Jean-Baptiste Coignard in two volumes. (4) The map, measuring 33.5 cm by 16 cm, was reproduced by Franz Ertinger and engraved by Pierre Michault. Instead of relying on the map's scale bar, I chose to use a different approach.

I used points of interest marked on the French map to calculate distances from a reference point, the São Pedro Church (labelled H on the map). The three points were the St. Jacobs Church in the Cochin-Chinese Settlement (G), the Dutch factory (K), and the port (O).

The distance from H to G on the map was 7.1 cm on Google Maps, it was 2.500 meters. 1 cm on the map corresponds thus to 352 meters.

The distance from H to K on the map was 2.6 cm on Google Maps, it was 816 meters. 1 cm on the map corresponds thus to 314 meters.

The distance from H to C on the map was 4 cm on Google Maps, it was 1.330 meters. 1 cm on the map corresponds thus to 332 meters.

The average of the three measurements above is 332 meters per 1 cm on the map.

The distance from H to I (São Paulo Church) on the map was 2.2 cm, which corresponds to an approximate distance of 730 meters between the two churches (2.2 x 332 meters) on Google Maps.

The initial calculation of the São Paulo church's centre was hypothetical, at a distance of 770 meters from the São Pedro Church. The new calculation still places the centre close to the earlier-estimated São Paulo grounds.

Something doesn’t align

My primary concern at present was the distance between the São Paulo Church and the point where the Takhian Canal (5) connects to the old Lopburi River (now the Chao Phraya River), since the French map shows the church quite close to the mouth of Khlong Takhian and the calculated position is not.

Until the 18th century, the Lopburi River was the main river surrounding the city, flowing all the way to Bang Sai, where it merged with the Chao Phraya River.
It was only in the mid-19th century that the Chao Phraya River was diverted to Ayutthaya and merged with the Lopburi River. The riverbanks on the west side of the city, as well as the banks between the city and Bang Sai, were possibly narrower than they are today, since the volume of water carried by the Lopburi River was probably less. A part of the river was diverted to the east side of the city at the end of the 16th century as part of the defences.

Also, Khlong Takhian, a man-made shortcut or "khlong lat" in the old Lopburi River used for boat traffic during the Ayutthaya era, was probably much wider than it is today. On de La Loubère’s map, there is a pretty large confluence at the junction of Khlong Takhian and the old Lopburi River. Today, this confluence is barely visible as the canal is mostly silted up and its mouth has shrunk, making measurement difficult.
I decided to use the Mouth of Khlong Takhian (MTK), specifically the south bank, as a reference point, just as I did for the São Pedro Church earlier.

The distance from MTK to H on the map was 3.4 cm on Google Maps, it was 1.400 meters. 1 cm on the map corresponds thus to 412 meters.

The distance from MTK to K on the map was 5.7 cm on Google Maps, it was 2.190 meters. 1 cm on the map corresponds thus to 384 meters.

The distance from MTK to G on the map was 9.5 cm on Google Maps, it was 2.815 meters. 1 cm on the map corresponds thus to 296 meters.

The distance from MTK to O on the map was 7.4 cm on Google Maps, it was 2.747 meters. 1 cm on the map corresponds thus to 371 meters.

The average of all the measured distances (352+314+332+412+384+296+371 / 7) is 352 meters.

Measured from the São Pedro Church (H), the São Paulo Church (I) is 2.2 cm on the map and should be at 2.2 x 352 = 774 meters on Google Maps, which is very close to the last calculation.

Measured from the Mouth of Khlong Takhian (MTK), the São Paulo Church (I) is 1.2 cm on the map and should be at 1.2 x 352=422 meters on Google Maps.

The last measurement suggests a second hypothetical location for the São Paulo Church, near the Islamic Sri Ayutthaya Foundation School, at approximately 14°19' 31.5" N 100° 34' 19.2"E.

There is, though, a discrepancy of 204 meters (774 + 422 = 1196 meters) when calculated as a straight line on Google Maps, likely due to map distortion.

Conclusion: Using the original French edition of de La Loubère’s map and adopting a different approach, I arrived at the same result as 15 years ago: a distance of approximately 770 meters between the São Pedro and São Paulo Churches. The new calculation shows 774 meters. Changing the reference point to the mouth of Khlong Takhian (not shown on the map legend) established a second location for the São Paulo Church. Only an archaeological excavation in the designated areas, or the use of LIDAR (Light Detection and Ranging), can verify whether one of the above results is correct.

Footnotes:

(1) Joaquim de Campos wrote "Early Portuguese Accounts of Thailand" (Antigos relatos da Tailândia), published by Camara Municipal de Lisboa (Lisbon City Council) in 1983, to commemorate Portuguese–Thai relations and preserve rare accounts of Ayutthaya from the 16th–17th centuries. Campos, Joaquim de (1940) - Early Portuguese accounts of Thailand. Journal of the Siam Society. 032-1b.

(2) Simon de La Loubère (1642-1729) studied law and became secretary to the ambassador in Switzerland, M. De Saint Romain. De La Loubère was sent on the second embassy to Siam by Louis XIV to convert King Narai to Catholicism. He departed from Brest on 1 March 1687 and arrived in Siam on 27 September 1687 CE. The embassy stayed for only four months. Simon de La Loubère's mission was a failure. He proved to be a keen observer in his account of his voyage.

(3) "À deux ou trois lieues au-dessous de la ville, sur le bord du fleuve, à main gauche, il y a un petit tertre que les Siamois appellent Baan Yesuit, c’est-à-dire le Village des Jésuites. On y voit encore deux marches de pierre, quelques briques & une fontaine d’eau bénite de pierre. Un peu plus haut, il y a un autre tertre semblable que l’on appelle Baan Yacobin, c’est-à-dire la Maison des Jacobins." [François-Timoléon de Choisy, abbé de Choisy (1644–1724 CE), in his book “Journal du voyage de Siam fait en 1685 & 1686,” published in Paris in 1687 CE].

(4) A second edition was published at the same time in Amsterdam by Abraham Wolfgang, a Parisian publisher who sometimes had works distributed through Amsterdam channels.

(5) Khlong Takhian is a still existent canal situated south of Ayutthaya's city island, running mainly through Pak Kran and Khlong Takhian sub-districts. The canal is named after the Malabar Ironwood, a tree often used for making boats and ship masts. The canal has its origin at the Chao Phraya River near the St Joseph Church in the former Cochin-Chinese settlement. It has its mouth further south, back in the Chao Phraya River, below the former Portuguese settlement and opposite the northern tip of Rian Island (Ko Rian). The canal was a man-made shortcut, or "khlong lat," between two stretches of the Chao Phraya River, used by boats to avoid the river's heavy current and the turbulent waters near the Bang Kaja confluence.

AYUTTHAYA HISTORICAL RESEARCH

THE SEARCH FOR THE SÃO PAULO CHURCH

(The drawing, created by Dr Joaquim de Campos, highlights the sites of several Catholic churches and a cemetery, indicating a historical Christian presence in the region - annotated by José Martins)

(The map in the English edition “A new Historical Relation of the Kingdom of Siam” published in 1693 CE)

(Adjusted position of the São Paulo Church – Based on de La Loubère's map, the grounds are 150 x 65 meters)

(The map on an A4 sheet shows a ground of 0.2 by 0.5 cm, which equals 65 x 150 meters)

(Detail of the São Paulo Jesuit Church from Jean de Courtaulin de Maguelonne’s map – 1686 CE)

(The map in the French edition “Du royaume de Siam” published in 1691 CE)

(Another possible position of the São Paulo Church)

(The Ruins of St. Paul's Church, the majestic granite façade of the 17th-century Jesuit church in Santo António, Macau - Picture taken August 1980)

When the past no longer illuminates the future, the spirit walks in darkness.
(Alexis de Tocqueville)

HISTORY OF AYUTTHAYA

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