I'm doing research for a book, and if there's a search term that would get me an answer to this question I can't find it.
Basically, I'm trying to determine if areas of knowledge like physics, chemistry, geography, anatomy/medicine, forging/metalwork, or even history itself was subject to any edicts regarding information sharing during the colonial era and, if so, how that was enforced. Obviously there would be the initial barrier of "the colonized people don't speak French," but eventually some would learn. At that point, you could lose the technological advantage which allows you to maintain control of the colony. This is basically what happened in Haiti, and colonialism persisted for over 150 years after that rebellion. It seems to me that the first thing you'd do is re-evaluate what information is allowed to reach the colonies, but I can find no evidence of this practice.
Were some books prohibited from being taken to the colonies? Were letters between scientists opened and checked for prohibited information before they left the nation? How did colonists with children cope with any such restrictions, if they existed, given their children still needed lessons from tutors?
Are there any incidences where knowledge spread to a population centre that had to be isolated or culled in order to maintain control over the larger body of people?
I will only talk about nineteenth century French colonies, and particularly Indochina.
The dilemma faced by French colonial authorities was the following.
The profitability of the colonies required skilled enough colonial subjects. This was true in settler colonies (North Africa) and perhaps even more in exploitation colonies (Indochina, West/Central Africa) where there were few colonizers and colonists, and where most of the work had to be done by local people: not only for the production of raw materials (agricultural products, mineral ore), but also for the production of manufactured goods (even if they were not exported), for service jobs, and for the military. For this, it was necessary to provide some level of instruction to the masses, and a higher level of instruction to the "elite" native people who would act as intermediaries between the colonizers and the colonized. In Indochina, for instance, the first indigenous schools were created for interpreters. There was also a propaganda aspect: French colonization was (outwardly) about its grand and noble "civilizing mission" and educating the natives was part of the "deal" of colonization.
But...
Colonial authorities feared - not without reason, as it turned out - that educating colonized people would lead to trouble. Note that there were similar concerns about educating the poor (who would stop working and revolt) or women (who would turn crazy or even sterile)! Nineteenth century authorities and political theorists were obsessed with the danger of déclassement: undeserving people who were given education would start thinking above their status, and, once they had failed to meet their desired position, they would become bitter, angry, and dangerous. In the case of African or Asian people, some colonial theorists advanced the idea that their brains were just not physically built for higher thinking and that force-feeding Western concepts to them would made them sick. Louis Vignon, professor at the Ecole Coloniale, 1919:
It is the case with ideas in the intellectual order as with chemicals in the physiological order: when they are absorbed, in any dose, by organisms for which they are not suitable, and in doses that are too high by organisms that can only withstand them, they result in fever, imbalance, or death.
As a result, there was a neverending debate between colonizers themselves, and between colonizers and native elites, about what should be taught to colonial subjects and to whom colonial subjects. By far and large, this was not about the dissemination of technologies or science, but of ideas. France was particularly vulnerable: the French Republic took its motto and ideological rationale from the French Revolution. One did not have to think hard to find that "Liberty, Equality, Fraternity" was at odds with the reality of the life of colonized subjects.
The main solution to this problem was to restrict education as much as possible, with an educational system shaped as a pyramid. There was a wide base consisting in pupils who received minimal schooling (basic literacy and practical subjects). Hard barriers were established to prevent them to proceed to the next step. Most of the education took place in schools for native students, who were taught curricula that praised France's "civilizing mission" and the aspects of local cultures deemed appropriate by French authorities. A history textbook from 1925, written for native Algerians and for children of colonists include 18 chapters (out of 22) about the colonization of Algeria. A 1936 edition actually contained critical assessments of some of darkest aspect of the conquest of Algeria but still praised colonization (Léon, 1991). The keyword was "adaptation": native students should be given an education adapted to them. This was actually a good idea from a pedagogical perspective (no "Our Ancestors the Gauls" nonsense here) but the goal was absolutely political.
The top of the educational pyramid was sparsely populated by a handful of extremely gifted students from trustworthy families. In Indochina, those top students actually went to same schools as the colonists, or went to study in France (like top students from North African/African colonies). This was good for colonial propaganda, but it caused endless headaches to French authorities. In 1933, a speaker at the Internation Congress of Anthropology told the story of the son of a Vietnamese mandarin who had come to Paris to pursue a doctorate about the French Revolution (La Mache, 1933):
How could such studies not have disturbed his brain? Two months later, he was reported as an agent of a secret society and taken under police surveillance.
In the thirties, Alexandre Varenne, Governor General of Indochina, noted that the students of the Lycée Chasseloup-Laubat in Saigon (which had both French and native students) had been given a Baccalauréat examination about "the causes and origins of the 1848 Revolution". He remarked:
It is perhaps not appropriate to teach the natives how revolutions are prepared and carried out.
In Indochina, this concern about the misuse of higher education resulted in the mid-1930s in the closing down of part of the Université Indochinoise (which was the only university established in the French colonial Empire attended by colonial students) and by stemming the flow of Indochinese students in France. The University was reopened and modernized during the war by the Vichyite governement of Admiral Decoux: by this time the concern about putting wrong ideas in the heads of students was secondary to the concern of students getting wrong ideas from the Japanese...
So I've only given a partial answer. There may have been other colonial situations where limitations were more straightforward, but in the French colonies, the main tool for information control was education, and this was hotly debated during the colonial period.
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