Here is the answer from my book "Christopher Columbus The Hero" Chapter 3:
Chapter 3. Discover, not “Discover”
The traditional story of Christopher Columbus tells us that he discovered America. However, revisionists want to discredit Columbus, not only with lies and innuendo but even with semantics! They want us to spell the word discover in quotes. When speaking about Columbus, in 2017, The Encyclopedia Britannica website spelled the words discoverer and discovery in quotations:
Columbus “has long been called the 'discoverer' of the New World, although Vikings such as Leif Eriksson had visited North America five centuries earlier… According to the older understanding, the 'discovery' of the Americas was a great triumph, one in which Columbus played the part of hero in accomplishing the four voyages.” 
But when talking about Amerigo Vespucci, the same Encyclopedia Britannica website spelled the words discovered, discovery, and discoverer without quotations: Amerigo Vespucci “is believed to have discovered the mouth of the Amazon River… The voyage of 1501–02 is of fundamental importance in the history of geographic discovery in that Vespucci himself, and scholars as well became convinced that the newly discovered lands were not part of Asia but a 'New World' … the newly discovered world be named 'ab Americo Inventore… quasi Americi terram sive Americam' ('from Amerigo the discoverer… as if it were the land of Americus or America').” 
Bias? I think so.
In 2016, MTV News said that Christopher Columbus “didn't discover America,” that “he landed in the Caribbean and never actually set foot in what is now American soil,” and that “the Vikings landed in America almost 500 years before Columbus.”  But, in the next sentence, the host blamed Columbus for mistreating native Americans. Question: How could Columbus mistreat native AMERICANS, when, according to MTV News, he never discovered the continent or “set foot in what is now American soil”? Contradiction? I think so. And if natives lived on the continent before the Vikings, then by the same faulty logic they didn't discover America either! In addition, Columbus indeed discovered the South American part of the continent, even though he never reached North America or settled in South America. So, the question is, how can Columbus be responsible for any conflicts in places he never reached, or places he never discovered or settled?
The deal is, there is a BIG, BIG, misunderstanding with the word discover. The word discover never meant “the first person to find desolate land” in Columbus’ historical context. The fact that Columbus was looking for a straight route to the Asian continent for trade, and to send missionaries to the “Great Khan,” meant that he was looking for inhabited land.
From Columbus’ own Journal:
“In that same month, on the information which I had given Your Majesties about the lands of India and a ruler known as the Great Khan (which means in Spanish 'King of Kings').”
Note: A ruler rules over people! Columbus continued:
“... Your Majesties... send me, Christopher Columbus, to those lands of India to meet their rulers and to see the towns and lands and their distribution, and all other things, and to find
out in what manner they might be converted to our Holy Faith; and you ordered me not to go eastward by land, as is customary, but to take my course westward, where, so far as we know, no man has travelled before today.”
“The Voyage of Christopher Columbus” translated by John Cummins, Prologue, page 81.
So you see, Columbus was looking for land already populated. This is what primary historical source, Bartolome de las Casas, wrote: “I understand that when he tried to find a Christian Prince to sponsor him, he was already sure that he would discover new lands and peoples… Columbus did not name it the Indies because it had already been discovered before, but because it was the eastern part of India ultra Gangem which, going East, was to the west of us since the world is round. No cosmographer had ever marked out the boundaries of India except those of the ocean.”
“History of the Indies” by Las Casas, Book One, Chapter 5, pages 20-21.
“India” was another word for Asia in Columbus’ time. Some people might be offended that Columbus called the natives, “Indians,” when they were not in “India,” or Asia; but Columbus might not be as wrong, as some may think, because those who were living in America before Columbus, somehow came here from “India,” or the Asian continent. I wonder why some people might be offended with Columbus calling the natives, “Indians,” but they are okay with the name, “Americans,” when that was not the name of the continent either! The name “America” came as a consequence of Co-lumbus’ discoveries, and Amerigo Vespucci (who the name “America” came from) was a contemporary of Columbus too.
All that Columbus wanted was to go straight from Spain to Asia, instead of sailing around Africa, like the Europeans were doing. That's basic children’s school history. I can't believe people forgot about that one. Columbus knew Asian land was already discovered by Asians, and he knew Europeans had traded there, which also means he was not looking to be the first European to reach India or Asia because again, he already knew Europeans had reached it. He was inspired by the travels of Marco Polo, so he knew a European already had reached China, in Asia.  So, those who bring Vikings to the conversation, don't know or understand what the word discover, or its historical context, means.
That's why it doesn't matter if Columbus knew about the Vikings reaching North America or not, because Columbus was aiming South, toward India, but also with the purpose of exploring the South Asian lands and islands Europeans had not reached yet, where, like Las Casas said, “no cosmographer had ever marked out the boundaries.” But of course, Columbus was not in South Asia, but in the Caribbean, and later on in South America. This makes him the first European to reach some of those places at such time.
So, what did Columbus discover?
1. Columbus discovered and proved, that one can sail safely and straight from Spain to the other side.
2. Because of him, and him alone, it was discovered later, that they were on another continent, and not in Asia.
3. Columbus is the one who brought two different worlds back together, after hundreds of years of lost communication.
4. He and those who follow after him discovered people and other lands Europe didn't know about for centuries.
5. Columbus was also the first European to explore the Caribbean, and probably the first European to reach Honduras, Nicaragua, Costa Rica and Venezuela.
To those of you who still insist Columbus didn't discover anything, who want to discredit Columbus accomplishments by playing semantic games blended with ignorance, to those of you who say, the native Americans were the ones who discovered America, because they were here first, I want to ask you the following questions:
1. What was the name of the native person who reached American land first?
2. What native tribe discovered America?
3. What year?
5. How did they get there?
6. What country did they come from?
7. Where did they settle first? North, South or Central America?
The fact is we don't know the answers to those questions, but we know the answers to the same questions when we are talking about Christopher Columbus. I also want to make a note about the Vikings: The Vikings sailed from Iceland and Greenland, which are very close to North America, while Columbus sailed straight west from Spain to America, which was farther and something people would not have dared to do back in those days. In fact, Columbus’ sailors were in tears, scared to death, as they left Spain into the unknown. They thought they were all going to die.
See “The Life of the Admiral Christopher Columbus by his son Ferdinand,” Chapter 18, page 48.
The Vikings quickly left America, not knowing they were on another continent. But let me tell you something, if the Vikings would have stayed there, impacting history like Columbus did, I would bet you, we would still be hearing the same complaints about the Vikings, as we hear today about Columbus. Remember, the Vikings were white, which is a crime to some revisionists; they also practiced conquest, war, raids, slavery, and rape; but the worst “crime” of all, was that the Viking who reached America, Leif Erikson, was a Christian!  Can you imagine the reaction revisionists might get once they find out this! They might stop bragging that the Vikings were the first doing anything! They might get a heart attack or something! They hate that “crime” more than any other. Like I said before, we would be still hearing the same objection today! On the other hand, I don't know why some people want to magnify the Vikings’ discoveries, which had no impact historically, and diminish Columbus’ discoveries, which have an actual historical impact.
In the words of Thomas A. Bowden: “Columbus did discover America--- for Europe. Prior to 1492, Europeans lived in total ignorance of the Western hemisphere and the people who inhabited it. Columbus and those who follow him lift that cover of ignorance--- they 'dis-covered' America. Once this knowledge had kindled Europe’s interest in the New World, European colonists came in growing numbers, bringing with them the wisdom of Western civilization in a vast westward movement, laying the groundwork for mankind's greatest political and economic achievement, the United States of America. Seen in this light, Columbus’s voyage is the one that truly made a difference historically.” 
“... it is significant that one never hears condemnation of the Vikings, or the Chinese, Japanese, Irish, or Welsh, or any other purported pre-Columbian voyagers, for having inaugurated centuries of 'ecocide' and genocide. By focusing all their attention on Columbus, his enemies confess their agreement that his voyage was the only one that mattered.” 
I would add to that, that we are here in the New World today, BECAUSE of Columbus and Columbus alone. Not because of natives, Vikings or anyone else, but because of Christopher Columbus.
1.Encyclopedia Britannica: Christopher Columbus Italian Explorer. Written by: Valerie I.J. Flint. Last Updated 1-14-2016.
2.Encyclopedia Britannica: Amerigo Vespucci, Italian Navigator, Written by: Roberto Almagià. Last Updated: 10-17-2011.
3.MTV News: “Columbus Was a Genocidal Rapist | Decoded |MTV News” Published on Oct 9, 2015.
4.“The Voyage of Christopher Columbus,” by John Cummins, Introduction, “The Orient and the Ocean Sea,” page 9.
5.“The Saga of Erik the Red,” Chapter “Eirik's family, and his son Leif's discovery of Vinland,” pages 23-27. Abela Publishing, London 2010
6.“The Enemies of Christopher Columbus” by Thomas A. Bow- den, page 27.
7.“The Enemies of Christopher Columbus” by Thomas A. Bowden, page 28.
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