True, the disease spread to the Aztecs greatly diminished their population, making them much easier to conquer.
The line was between Spain and Portugal, dividing the Americas between the two. Spain received Central America and most of South America, while Portugal receiving the portion of South America containing most of Brazil.
It was significant because it changed how people were represented, meaning that more people got suffrage rights and "rotten burroughs" were removed to prevent extremely rich people from places where there's not many people to have high electoral power. The idea that only house owners can vote was changed to anyone who lives in the UK.
Regarding this subject of History some comments:
In the 1840 Americans began their mayor push west of the Mississippi into lands that were largely unsettled except by the indigenous tribes.
Some went in search of land, some were in search of gold and silver and in the case of mormons in search of religion freedom.
During this time the city that grew to over 4000 people was santa fe.
