The best answer for the question: According to "Make it New": Early modernism, which type of traditional poetry influenced early modernist poets, would be: the Haiku.
Explanation:
The Haiku is originally a traditional type of Japanese poetry that is characterized by its simplicity in the free-verse form-style it uses, and also that it is pretty short, its purpose only being to show a fleeting moment in time, often of nature. This simplicity, and the style used in Haiku called the attention of one of the precursors of modernist poetry: Ezra Pound, who initiated the maxim "Make it new" as a way to describe what modernist poets, and writers in general, be it of prose or verse, wanted to accomplish and portray through their writings. The Haiku offered this simplicity and thus had a big influence on a lot of the early modernist poets like Pound, and others.
This caused him to discover suffering in the world after a sheltered life and he left the palace and his father behind to discover the truth of suffering