Mao in 1949 became ruler of one of the poorest countries in the world. A land whose sovereignty had not been respected since the First Opium War.
I’ve done a detailed account showing what actually happened. On-line at this website.
When he died in 1976, China was much less poor. It had in fact grown faster than the USA or India in the same period. See https://labouraffairsmagazine.com/recent-issues/2019-11-magazine/2019-11/ for details.

The overall effect of his 28 calendar years of power was much longer Chinese lives. The entire Global South made progress, but China was the most successful.

Most Western books and reports hide most of the evidence and mention only a setback in the years 1958 to 1961. It was a failure based on the same methods that succeeded both before and afterwards:

Read my page to find what really happened.