Growing up I had always heard stories of Mexican oppression and the need for an Anglo-white Republic that better represented the population. It's not hard for me to look back at some of the fanciful ideas that informed a mythology dominated by the events of the Alamo and leadership of Sam Houston.
I generally steer clear of the mythologies I grew up with- but I recently had someone ask my about this particular event and I realized I didn't have a good answer for them. Cursory research into trusted sources puts the emphasis for Texas secession clearly on the issue of slavery and the potential economic prosperity provided by the expansion of cotton industries and settlement/investment provided by the southern plantocracy.
But I'm curious how this actually weighs out- what historians of North America or early (is this considered early?) US history might have to say. Certainly interested in secondary source recommendations if there is anything noteworthy.
So why did Texas secede from Mexico?
Something that always bothers me about this is we tend to try to put the cause in the context of the resulting government.
I highly suggest reading the texas declaration of independence. Basically most our the periphery states at the time were pissed at centralization. Mexico was acting like a dictator.
The direct cause was Mexican politics, its why we fought together with the Republic of Yucatan at Campeche.( well and they paid us).
The declaration doesn't mention slavery and it wasn't a direct cause. But that doesn't mean it wasn't a thing the new constitution certainly cemented it in place.
But it's hard to argue a slavery primacy case. Really it was an escalation. A minor group in fredonia revolted. The Mexican army came in, but it was a minor revolt and most remained loyal. But the Mexicans assumed US agitators. And their actions pushed more over to the rebel ideology.