What is the fine-grained topic of the following text: The bitter struggles of the Long March, which was completed by only one-tenth of the force that left Jiangxi, would come to represent a significant episode in the history of the Communist Party of China, and would seal the personal prestige of Mao and his supporters as the new leaders of the party in the following decades. Only return the topic.
The Long March's significance in the history of the Communist Party of China and Mao's leadership.