"...the French Orient was not just any colony; Paris's design upon it was to have it by to the French Empire what India was to the British, the crown jewel in its great expanse of global territories and a territory ripe for economic exploitation. The level of investment directed in that direction, then, was commensurate to that. One of France's advantages was its reliance on a robust local bureaucracy that was more tolerant of local norms than the one Britain had built from the ground up in the Raj; Chinese-style examinations were still carried out in both Hainan and Formosa, and the Nguyen Emperor in Annam and Tonkin still held considerable local control under the watchful eye of the Governor-General of French Indochina, whose seat was moved to Hanoi in 1900 to be closer to Kwangchouwan, Port-Napoleon and Kiungchow. [1] Machine parts assembled in France and exported helped drive an agricultural revolution with mechanized farming in the plantation-heavy economies of Cochinchina and Hainan, new factories were underwritten in the growing light industry of Tonkin and Formosa, and the tentacles of Credit Maritime seemed everywhere, leading some British officials to joke that the French had former their own East India Company, decades after such an endeavor was fruitful any longer. Indeed, the Golden Sail's offices were the financial and commercial centers of the French Orient; its office in Tai Pei, the capital of Formosa, was built in the style of a grand Chinese pagoda, while its Hanoi location took up three city blocks and was built in the noted French colonial style, both edifices lavish and broadcasting the tremendous power of France's leading financial institution overseas. [2]
France was hands-on with its colonies' cultural development, too. In Formosa, Hokkien Chinese was the co-official language alongside French, to set the island apart mentally and linguistically from more common Peking, Shanghai or Canton dialects of the language; in Hainan, an even more aggressive course of social engineering was pursued, with the indigenous Li people receiving the most choice bureaucratic positions and their language being raised to be co-official, to the point that Cantonese Chinese was discouraged in the dozens of schools established on the island by the eve of the Boxer War.
Furthermore, the French Orient became a sandbox for Catholic missionaries, indeed one of the most highly-preferred places for both lay organizations and clerics to proselytize. Catholicism long enjoyed a robust foothold in Korea, particularly in the Taedong Valley and Pusan, but there had to compete with not just the native Buddhism but Russian Orthodox and American Methodists, Quakers, Baptists, Anglicans and Presbyterians both for religious converts as well as the traditional position of the Church in education. In the more closed, captured societies of the French Orient, though, there was no such contest for the faith - unlike in France, where the government had to pay lip service to a large secular populace, the Church enjoyed free reign. By the early 1900s, after only fifteen years since the Treaty of Tientsin, Catholic institutions had monopolized elementary and secondary instruction in all four French colonies, and in 1899 the first university opened in Saigon (the Catholic University of Cochinchina) and a year later Formosa Apostolic University, also Church-run, opened near the grand construction site of the new Tai Pei Archdiocese and its accompanying cathedral.
The acquiescence of many locals was practical; relatively few Frenchmen resided in the Orient (compared to the much larger British population in the Raj) but a strict religious caste system mirrored on the Code de l'Indigenat in Algeria reigned: Christians at the top (in practical terms, just Roman Catholics, especially French ones), everybody else below. Catholicism was a ticket to success in French Oriental society, particularly in urban centers such as Saigon, Hanoi, or Tai Pei. Legally speaking, there were few substantive distinctions between white Catholics and Asian ones (culturally, there was a fair amount of discrimination) [3], which was also a large factor in a number of baptized Vietnamese, Hainanese and Formosan subjects making their way out of their homelands into the broader French Empire. The Marine Imperiale always needed sailors, the Foreign Legion always needed riflemen. French industry already attracted immigrants from Italy and Spain, as well as North Africa; before long, Franco-Oriental subjects joined them too on the Metropole's soil, where they found ethnic enclaves and communities in Paris, Marseille, Lille, Lyon and other great cities to give them a small slice of home. While Buddhist or local pagan women were dismissed as being good for little more than whorehouses in Saigon, Kiungchow or Kwangchouwan, Catholic women were brides for soldiers or lay missionaries after their time abroad who would return with them to France to give birth to the next generation. [4] In that sense, it was not entirely the economy that was exploited by Paris abroad - the people were used for France's national mission just as much..."
- The Scramble for Asia: Colonialism in the Far East in the 19th Century
[1] Modern day Qiongshan, the main city on Hainan
[2] Of course, the Banque de l'Indochine is still a thing; the Golden Sail is a global institution
[3] This has been a French thing for some time in OTL too; the tradition of the Foreign Legion is probably a big part, and Napoleon had black officers who fought for him.
[4] French natalist concerns are lessened by this phenomenon, to be sure.