good try, nonetheless
monte around = primary target
did you whip all you could?
it's just not normal that tokugawa should have anything but a few archers in his cities when you storm in.
2 possibilities:
- not early enough for the rush (not enough whipping)
- too distant opponent (bad target)
And what cleverhandle said is true. In an early assault you won't be able to get more than 2 cities (not including barb cities). So you want to attack when the AI has only 2 cities

ANd don't worry about extortion of techs. In fact you shouldn't have alphabet yet. If you have, you waited too long for the assault.
Any way, 4 cities built = no early rush.
If you have time to build 4 cities, the monarch AI will have 5/6 cities. No way to just storm through.
So we're back 2 options :
1- early war against a 2 city Civ
2- not so early war to conquer 2 more cities.
If it's option 2, you don't want to fight toku. He never trades techs (well, almost never), and i never could extort anything but gold or map from him.
For learning sake i would try the same game (you saved at some point, didn't you?) with either option 1 or option 2 vs Montezuma.
Tokugawa isn't a total psycho but he will backstab you if you drop on power, so don't drop low on power!