"America, Africa, the Middle East and Asia" - That include the known and the unknown world, at that age.
When I referred to half world, expressed in the Tordesilhas treaty, that specifies the following:
Signed in Tordesilhas, Castile, on June 7th of 1494, agreeing to divide the "New World", yet to be discovered, along a north-south meridian 370 leagues (1770 km) west of the Cape Verde Islands (off the coast of Senegal in West Africa). The lands to the east would belong to Portugal and the lands to the west to Spain.
So that means, was a division of the world, considering the known world (because no one was supposed to know about the unknown world, right? Else it wasnt unknown), but was targeting the unknown world also (whatever that would be
). That only exclude for the possessions of the two parts

ortugal and Spain, the land belonged already to the catholic countries.
In practical terms was a division of the hemisphere in two. Here you have, half of the world. Now you name it what you want
The permission, the intention, and in a great scale what really happen after, was the exploration, colonization, and conquest of almost all the valuable lands (like Brazil and some possessions in Africa and India) that were in the our half of the world.
So of course, more than sq miles, was the resources and the value of lands that were in cause. As example you have Brazil.
Anyway everyone here consider also the England empire great, though not so great in those times.
And my point is, considering two millions ppl of that age, proportionally I dont think England grab so much land, after in those golden ages. (since England already have much more than 8 million ppl on those times, (4x more land, following your thoughts).
So, if you beat us? Considering this rate, you dont
but who cares? (we still beat you in soccer last eurocup).lol 
Besides, some Portugal contribution to you It was the Portuguese that introduced the habit of drinking tea in England.
It was Catherine of Braganca, who married King Charles II of England in 1662. She took with her as a dowry the city of Bombay - the starting point for the British colonization in India - as well as some leaves of Chinese tea, that was worth a fortune in that time.
And concerning slaves trading, yes Portugal was one of the merchants of those goods. I am sorry the language, it is totally wrong obvisouly in our age (and morally in all ages) but, in those times, was not only Portugal or Spain that trade slaves. All do! No European country see that a problem. And If Portugal had the resources to trade (Africa), others buy it from us
(Like England for instance.) Years later also you get that resources directly.
Anyway, if human right is concerned, in other way, Portugal was the first country to abolish the death penalty - This dates back to 1867 when Portugal led the way immediately followed by the Netherlands. Sweden and Denmark joined this abolitionist movement after the World War I, and after the World War II Finland, Austria, Italy did likewise. More countries would follow, but Portugal was the leader.
And also, other human right achievement: there was a Portuguese who saved 16 times more jews than Oskar Schindler
Schindler was an ordinary man with an extraordinary power who saved 1200 human lives during the Holocaust of World War II. Steven Spielberg immortalized his name with the Movie "The SCHINDLER's list" that Hollywood produced a few years ago.
Yet, even though we should ALL pay our tribute to all the Jews who were saved by the humans actions of Schindler, did you know the name of the ONE Portuguese man who saved over 30.000 Jews to escape Nazi persecution, issuing visas against the orders of his government?
NOTE: If you think about it that's enough people to fill most regular sized football stadiums! His name was Aristides Sousa Mendes, and he was the Portuguese consul in Bordeaux.
Getting back to the main subject, what I corrected from my first statement, besides explain myself in a detailed way?
