North America is a continent entirely within the Northern Hemisphere and almost all within the Western Hemisphere. It can also be considered a northern subcontinent of the Americas.〔(【引用サイトリンク】North America )〕 It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the west and south by the Pacific Ocean, and to the southeast by South America and the Caribbean Sea.
North America covers an area of about 24,709,000 square kilometers (9,540,000 square miles), about 16.5% of the earth's land area and about 4.8% of its total surface.
North America is the third largest continent by area, following Asia and Africa,〔(【引用サイトリンク】title=North America Land Forms and Statistics )〕 and the fourth by population after Asia, Africa, and Europe.〔(【引用サイトリンク】title=North America Fast Facts )〕
In 2013, its population was estimated at nearly 565 million people in 23 independent states, or about 7.5% of the world's population, if nearby islands (most notably the Caribbean) are included.
North America was reached by its first human populations during the last glacial period, via crossing the Bering land bridge. The so-called Paleo-Indian period is taken to have lasted until about 10,000 years ago (the beginning of the Archaic or Meso-Indian period). The Classic stage spans roughly the 6th to 13th centuries.
The Pre-Columbian era ended with the arrival of European settlers during the Age of Discovery and the Early Modern period. Present-day cultural and ethnic patterns reflect different kind of interactions between European colonists, indigenous peoples, African slaves and their descendants. European influences are strongest in the northern parts of the continent while indigenous and African influences are relatively stronger in the south. Because of the history of colonialism, most North Americans speak English, Spanish or French and societies and states commonly reflect Western traditions.
The Americas are usually accepted as having been named after the Italian explorer Amerigo Vespucci by the German cartographers Martin Waldseemüller and Matthias Ringmann.〔(【引用サイトリンク】title= Amerigo Vespucci )〕 Vespucci, who explored South America between 1497 and 1502, was the first European to suggest that the Americas were not the East Indies, but a different landmass previously unknown by Europeans. In 1507, Waldseemüller produced a world map, in which he placed the word "America" on the continent of South America, in the middle of what is today Brazil. He explained the rationale for the name in the accompanying book ''Cosmographiae Introductio'':
''ラテン語:... ab Americo inventore ... quasi Americi terram sive Americam'' (from Americus the discoverer ... as if it were the land of Americus, thus America).
For Waldseemüller, no one should object to the naming of the land after its discoverer. He used the Latinized version of Vespucci's name (Americus Vespucius), but in its feminine form "America", following the examples of "Europa", "Asia" and "Africa".
Later, other mapmakers extended the name ''America'' to the northern continent, In 1538, Gerard Mercator used ''America'' on his map of the world for all the Western Hemisphere.〔(【引用サイトリンク】title=The Naming of America: Fragments We've Shored Against Ourselves )〕
Some argue that the convention is to use the surname for naming discoveries except in the case of royalty and so a derivation from "Amerigo Vespucci" could be problematic. Ricardo Palma (1949) proposed a derivation from the "Amerrique" mountains of Central America—Vespucci was the first to discover South America and the ''Amerrique'' mountains of Central America, which connected his discoveries to those of Christopher Columbus.
Alfred E. Hudd proposed a theory in 1908 that the continents are named after a Welsh merchant named Richard Amerike from Bristol, who is believed to have financed John Cabot's voyage of discovery from England to Newfoundland in 1497. A minutely explored belief that has been advanced is that America was named for a Spanish sailor bearing the ancient Visigothic name of 'Amairick'. Another is that the name is rooted in a Native American language.〔
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』