Stipulations:
Should be a real Empire- i,e a super-populated region-spanning multinational entity dominated by a Khmer Administration, unlike the OTL 2008 "Empire of Japan", merely ruled by an emperor
Should Modernize and be equal of OTL Europe in technology.
==============
I guess you can begin it with the Khmer conquering and Assimilating the Siamese
early on, so they don't become a problem.
Should be a real Empire- i,e a super-populated region-spanning multinational entity dominated by a Khmer Administration, unlike the OTL 2008 "Empire of Japan", merely ruled by an emperor
Should Modernize and be equal of OTL Europe in technology.
==============
I guess you can begin it with the Khmer conquering and Assimilating the Siamese
early on, so they don't become a problem.