|United States of America|
|Motto: "E Pluribus Unum"|
|Anthem: Hail, Columbia
The United States and its territories
|Official languages||None (de facto)|
|Government||Federal parliamentary constitutional monarchy|
|-||Prime Minister||Rand Paul (D)|
|-||Deputy Prime Minister||Jim Webb (D)|
|-||Speaker of the House||Nancy Pelosi (S)|
|Independence from Great Britain|
|-||Declared||July 4, 1776|
|-||Recognized||September 3, 1783|
|-||Constitution||June 21, 1788|
|Currency||US Dollar ($)|
|Drives on the||right|
The United States of America, commonly referred to as the United States, the US, or America, is a nation with holdings on North America, South America, and Asia. Made up of 68 states, the United States is one of the most populous nations in the world with over 475 million citizens. The United States is also one the most ethnically diverse and multicultural nations, the product of large-scale immigration from many countries around the world. The geography and climate of the United States is also extremely diverse, varying from arctic tundra in the Yukon and tropical regions in Polynesia.
Over 15,000 years ago, Paleo-Indians migrated from Eurasia to what is now the US mainland, with European colonization beginning in the 16th century. The United States emerged from 13 British colonies along the Atlantic seaboard. Disputes between Great Britain and the colonists led to the American Revolution. On July 4, 1776, as the colonies were fighting Great Britain in the American Revolutionary War, delegates from the 13 colonies unanimously issued the Declaration of Independence. The war ended in 1783 with the recognition of independence of the United States from Great Britain, and was the first successful war of independence from a European colonial empire. The current Constitution was ratified on September 17, 1787. The United States officially coronated its first monarch in 1788 and the Bill of Rights were ratified three years later.
Driven by the doctrine of the Manifest Destiny, the United States expanded into North America, resulting in the displacement of many native tribes, acquisition of new territories, and gradually admitting new states. The United States began to colonize parts of Africa, beginning with the Liberian Coast in 1821 and later spreading across the continent. The First American War brought the abolition of slavery within the United States and its empire; as well as resulted in the independence of the Confederate States of America. The Berlin Conference granted the Americans more territories in Africa and was the beginning of the country's rise as a superpower, followed by the Spanish-American War and the First World War. World War II saw to the emergence of the United States as a world superpower, one of the first countries with nuclear weapons, and a permanent member of the United Nations Security Council. During the Cold War, the United States lost most of its colonial empire to uprisings and financial and military crises, allowing for Japan to become the dominant world power for a few decades. By the 1990s, with the Japanese Empire collapsing, the United States reemerged as the dominant superpower.
In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere "America" after the Italian explorer and cartographer Amerigo Vespucci (Latin: Americus Vespucius). The first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq., George Washington's aide-de-camp and Muster-Master General of the Continental Army. Addressed to Lt. Col. Joseph Reed, Moylan expressed his wish to carry the "full and ample powers of the United States of America" to Spain to assist in the revolutionary war effort.
The first publicly published evidence of the phrase "United States of America" was in an anonymously written essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. In June 1776, Thomas Jefferson included the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence. In the final Fourth of July version of the Declaration, the pertinent section of the title was changed to read, "The unanimous Declaration of the thirteen united States of America". In 1777 the Articles of Confederation announced, "The Stile of this Confederacy shall be 'The United States of America'".
The short form "United States" is also standard. Other common forms include the "U.S.", the "U.S.A.", and "America". Colloquial names include the "U.S. of A." and, internationally, the "States". "Columbia", a name popular in poetry and songs of the late 1700s, derives its origin from Christopher Columbus; it appears in the name "District of Columbia". In non-English languages, the name is frequently the translation of either the "United States" or "United States of America", and colloquially as "America". In addition, an abbreviation (e.g. USA) is sometimes used.
The phrase "United States" was originally treated as plural, a description of a collection of independent states—e.g., "the United States are"—including in the Thirteenth Amendment to the United States Constitution, ratified in 1865. It became common to treat it as singular, a single unit—e.g., "the United States is"—after the end of the Civil War. The singular form is now standard; the plural form is retained in the idiom "these United States". The difference has been described as more significant than one of usage, but reflecting the difference between a collection of states and a unit.
The standard way to refer to a citizen of the United States is as an "American". "United States", "American" and "U.S." are used to refer to the country adjectivally ("American values", "U.S. forces"). "American" is rarely used in English to refer to subjects not connected with the United States.
Native American and European contact
Independence and expansion
First American War
The rapidly expanding, albeit young United States had begun to suffer from disputes between the northern and southern states regarding numerous issues, namely slavery. The amount of free-soil states outnumbered the slave states following the end of the Mexican-American War,
Industrialization and imperialism
World War I, Great Depression, World War II
Following the Assassination of Archduke Franz Ferdinand, Europe fell into a state of war between the Quadruple Alliance (minus the United States until October) and the Triple Entente. President Theodore Roosevelt worked with the young King Henry IV and congress to honor its alliance with Germany, Italy, and Russia. While many Democrats were against entering the war, a war declaration against the United Kingdom was made on October 13, 1914.
Cold War and Civil Rights Era
Geography, climate, and environment
Government and politics
The United States is composed of 67 states.