First half of the 19th Century saw the emergence of a modern society all over the world beginning from Britain and spreading to the rest of countries.
United States was the flag bearer of Modernization in its truest sense.
The advent of Industrialization
Technology
Modern Science
Economic developments
Voting rights to women
Art
The rise of modernism was in contrast to the traditional societies within the Western world. Common people especially the indigenous population could not cope with the latest advancements as they adhered to their primitive practices. For example- Farming with bullocks was replaced by machines which was not eagerly welcomed in the South.
Maybe the better question to ask him is why he appointed his own bishop when the Pope is who does that. Why he thought could be more than the leader of the Church. What he intended, and why he turned back on his actions.