mar 12, 1925 - Sun Yat-Sen dies.
The death of GMD leader Sun Yat Sen causes a power struggle for the position of his leadership. Mao would not be in contention for the position yet, with frontrunners being Chiang Kai Shek (military and political leader of the KMT) and Communist, Wang Jingwei.
Added to timeline:
Mao's rise to power