Just an observation, if the Confederation of Texas, however it logically arrived at those borders, is as mapped, it would mean it lost a conflict/war over establishing a port on the Pacific. And it would mean they would be coming back for a second, third, etc., to attempt to seize territory on the Pacific in the future.
I find it strange that the St. Lawrence river is Quebec's border: it should be it's heartland. Losing the south-east shore just seems absurd.
As far as naming goes, it is very unlike it would be called "Quebec" at all. It would either be called Canada or New France depending on the status of the other French provinces at the time of independence.
And the greathing about alternate histories for North America is that they could have so very nearly become a reality. Texas was a nation once for example, and I wouldn't put it past the people of Quebec to becone a state in and of themselves.
In fact, I'd wager that the world would be much more interesting if this had actually happened.
Well so was I. In fact Im still here. I make alt. history maps myself, many about Texas,and this Texas seems implausible.
Based on the small amount of information given, the POD of this map is probably set between 1763 and 1803, between the end of the 7 Years War and the Louisiana Purchase. Texas didnt gain its independence from Mexico until 1836 and Austin wasn't founded until 1839. The Mexican-Amrerican War wasnt fought until 1846, and since it was never fought hear at all, the Texan-Mexican borders shown here, a result of the Mexican Cession and the Gadsen Purchase, are impossible.
Like I said, the southern border is impossible. That border wasnt established until 1846, 43 to 83 years after the Point of Divergence. It cant just be a "different Texas". It has to make sense in the historical context.