Why did the groups want to join Miguel hildago?

For 300 years, New Spain had been the most loyal and stable of all of Spain’s American colonies. But once the French Emperor Napoleon’s military juggernaut rolled across the Iberian Peninsula, and Spain’s North American colonists learned that a Bonaparte—Napoleon’s brother Joseph—sat on the Spanish throne, everything changed. Clandestine literary clubs sprang up, attracting restless or openly rebellious men. Flying every ideological flag, they hatched countless conspiracies, from liberating New Spain from Napoleon, to saving it for Ferdinand VII (the “rightful” Spanish king), to demanding outright independence. One near-miss revolt was scotched by Spanish Royalists, but a dozen more were floating on the wind, especially in the Bajío, where Hidalgo’s conspiratorial clique gathered.

Explanation: hope this helps