Pacific War:

Japan sponsored several puppet governments, one of which was headed by Wang Jingwei. However, its policies of brutality toward the Chinese population, of not yielding any real power to these regimes, and of supporting several rival governments failed to make any of them a viable alternative to the Nationalist government led by Chiang Kai-shek. Conflicts between Chinese communist and nationalist forces vying for territory control behind enemy lines culminated in a major armed clash in January 1941, effectively ending their co-operation.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". Who was the leader of the Nationalist government?
Chiang Kai-shek