Rush Tarquin
Gone Fishin'
The challenge is for a war between Brazil on one side and Britain and/or France on the other. The war must occur sometime between 1835 and 1845. Slavery cannot be a factor in the war. The POD must be 1785 or later.
The French claimed a big lump of Brazil as a part of French Guiana, though they only claimed it much later than your POD so... I'm unsure if it'd be a potential POD in your timescale.
The challenge is for a war between Brazil on one side and Britain and/or France on the other. The war must occur sometime between 1835 and 1845. Slavery cannot be a factor in the war. The POD must be 1785 or later.
The second possibility would be as result of the growing pressure of Great Britan over Brazil to end the African slave trade.
Read the OP. Slavery is off the table.
wolf brother's idea seems the best so far. French scientists were the first to "discovery" gum rubber and that, plus the prospect of other natural resources, led to a long term French interest controlling a chunk of the Amazon.
Spark an earlier demand in gum rubber, add a French government initiative much like the later UK one to assure supplies, mix in a little Fordlandia, fold in domestic political shenanigans, and you've got France tussling with Brazil over the issue of extraterritorial rubber plantations.
Someone's been reading my notes for TSPD I see![]()