First of all, the Spanish (along with the rest of the large European countries at the time) had guns and other military technology. With the advantage of having gunpowder, the Spanish were able to relatively easily conquer the indigenous peoples in the Americas. Another point is the Spanish military training; the American civilizations had no military training that matched the strict codes of the European countries, so the precision of the Spanish helped them conquer.
they declared their loyalty to france
The Harrison Land act took place on April 15, 1800. And was aimed towards giving people the right to buy land in the northwest territory. Hope this helps!