Question

why did the french build canals systems in vietnam

Answer 1

1.To increase the rice cultivation in the Mekong delta region.
2.And by 1931,Vietnam became 3rd largest exporter of rice in the world.

Answer 2

French built canal system in Vietnam because it was considered as best suitable place for rice production and plantation of other crops.  

Explanation:

It is because the majority of land in Vietnam was highly fertile. For the steady supply of common assets and other fundamental merchandise colonies used to add different nations and the same custom was trailed by French too.  

To build development in Vietnam the French began to extend its domains and started assembling waterways and depleting lands in the Mekong Delta. The tremendous arrangement of water system works, canals and earthworks-worked with constrained work, expanded the creation of rice development.