"The" is required before "Industrial" - you absolutely cannot leave it out here. There are myriad situations in English where articles are or are not required, and there are no rules that cover all the situations - you just have to learn the situations by experience. However, there is a "rule" of sorts for articles (invented by me).
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wangqh2696122 In the following sentence, should we use "the"? What's the rule? The most important thing about cotton in history is the part it played in ______Industrial Revolution.
wangqh2696122What's the rule?You need "the". It's the only Industrial Revolution that there is.