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United States of America

United States of America

Type of Government

The United States is governed as a federal constitutional republic. The U.S. Constitution divides political power between the federal government and state governments and between three coequal branches of the federal government: executive, legislative, and judicial. The president serves as both the head of state and the head of government. The Congress, the chief legislative body, consists of the House of Representatives and the Senate.


The United States is the fourth-largest country in the world, occupying more than half the continent of North America as well as the northwestern state of Alaska and the island state of Hawaii in the Pacific Ocean. The U.S. mainland (forty-eight contiguous states) is bordered by Canada to the north, Mexico to the south, the Pacific Ocean to the west, and the Atlantic Ocean to the east. The nation’s capital is Washington, located in the District of Columbia. The United States is a federation of fifty states. In addition, a number of unincorporated territories (referred to as possessions or overseas territories) are governed under U.S. law, including American Samoa, Guam, Puerto Rico, and the U.S. Virgin Islands.

Before the arrival of European explorers, North America was settled by many Native American tribes who lived in what is now the continental United States for thousands of years. European exploration of the Americas began in the late fifteenth century, when the Italian-born explorer Christopher Columbus (1451–1506), in the employ of the Spanish Crown, first landed in the West Indies. The Spanish and Portuguese explorers who followed were lured by the riches of South America; Europeans did not turn their attention to North America until the second half of the sixteenth century.

England lagged behind its European rivals in colonizing the Americas, but it was the English colonies that would ultimately prosper in North America. Beginning with the settlement of Jamestown, Virginia, in 1607, England established colonies along the Atlantic seaboard throughout the seventeenth century. Settlers came to the colonies with a variety of motives: easy wealth, cheap land, adventure, religious freedom, and escape from political persecution. Some migrants, though, had no choice: English prisoners were shipped across the Atlantic as indentured servants and Africans were sold into slavery.

The English colonies developed along two broad patterns. The southern colonies thrived on staple crop exports—primarily tobacco and rice—and relied on large numbers of indentured servants and, later, African slaves for their labor. The northern colonies developed more diversified economies based on commercial grain farming, fishing, manufacturing, and shipbuilding and depended primarily on family and wage labor, though slavery was not unknown. All the colonies developed a strong tradition of self-government. By the mid-seventeenth century each of the thirteen colonies had a representative assembly. Colonial governors, executive councils, and judges were appointed by Britain, but their salaries were paid by the elected colonial legislatures, ensuring their deference to popular will. More important, the colonial legislatures regarded internal governance as their own territory, not the British Crown’s.

In the 1760s the British Parliament began to encroach on the powers of the colonial legislatures and sought to raise revenues for its depleted treasury by taxing the colonies. Beginning with the Stamp Act of 1765, which imposed a tax on all printed materials, American colonists faced unprecedented taxation. In the past, the colonists had paid customs taxes levied by the British Empire, but direct taxation had always come from the colonial legislatures, not Parliament. The colonists reacted swiftly, passing antitax resolutions and banding together to present their objections to the king. The uproar eventually led Parliament to restrict the powers of the colonial legislatures—a move that pushed the colonists toward independence.

At the First Continental Congress, which convened in Philadelphia in 1774, colonial delegates met to discuss plans for achieving American independence. They adopted a declaration of rights that asserted home rule and denounced “taxation without representation.” By the time the Second Continental Congress convened the following year, the first battles of what would become the American Revolution (1775–1783) had already begun.

The central accomplishment of the Second Continental Congress was the Declaration of Independence, which was drafted by the Virginia aristocrat Thomas Jefferson (1743–1826) and adopted by the colonies in 1776. The declaration outlined the colonies’ grievances with Britain, but the basis of the war for American independence was the fundamental right to self-government: “We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty, and the pursuit of Happiness.”

The demands of fighting the American Revolution required coordination and a permanent union between the former colonies, and to that end these nascent states adopted the Articles of Confederation in 1781. Reflecting the colonists’ fear of authoritarian rule, the government under the Articles was decentralized—there was no executive or judicial branch. The legislature, however, had broad powers, including the conduct of foreign affairs and war, regulation of the postal service, control of Native American affairs, and the power to borrow money. The chief shortcoming of the articles, however, was that Congress lacked the power to tax, and thus the burden of war funding fell on the states. By the end of 1786 the government had broken down, and the young republic faced economic depression, indebtedness, and rebellion.

State governments sent delegations to Philadelphia in the summer of 1787 to deal with these challenges. Most of the delegates had modest expectations for the convention—the resolution of trade disputes among states, the formulation of a national trade policy, and minor revisions to the Articles of Confederation—but James Madison, who was the leader of a group of Virginia nationalists, envisioned a completely new American constitution.

Madison’s initial proposal recommended a powerful national government with the authority to override state laws, a bicameral (two-chambered) legislature favoring the most populous states, and an executive branch elected by the legislature. This proposal did not appeal to smaller states and to those wary of central government. Even though Madison’s original plan did not survive, he achieved his goal of adopting a new constitution for the nation.

The states reconciled their differences by striking a Great Compromise: state equality would be preserved in the Senate, whereas larger populations would be rewarded with greater representation in the House of Representatives; the executive would be elected by an electoral college, not the legislature; and powers would be divided between the central government and the states. Additionally, the matter of slavery, long a point of contention between the northern and southern states, was sidestepped by a compromise measure—representation would be based on each state’s free population plus three-fifths of its slave population—that sowed the seeds of future conflict.

The new constitution faced stiff resistance in the states. It was only after Federalist supporters promised to amend the new constitution with a Bill of Rights—provisions guaranteeing certain basic freedoms—that it was ratified by the states on June 21, 1788. The new U.S. government commenced on March 4, 1789, and the Bill of Rights was ratified on December 15, 1791. The structure and principles of government laid out in the Constitution set the stage for more than two hundred years of democracy in the United States.

Government Structure

The United States is governed as a federal constitutional republic. The structures and functions of government are outlined in the Constitution. According to the Constitution, political power is derived from the people and vested in the government. This power is divided between the federal government and state governments and between three coequal branches of the federal government: executive, legislative, and judicial.

The framers of the Constitution, mindful of the failures of republican governments in ancient Greece, the Roman Republic, and Renaissance Italy, sought to limit the power of the central government. Thus, the political structure outlined in the Constitution preserves individual freedom and state sovereignty and ensures that power is not concentrated in the hands of the few. These goals are achieved through the federal system of governance, the separation of powers, and the Bill of Rights.

The exercise of government power is first limited through a federal system of governance. The Constitution assigns specific powers to the federal government and delegates the remaining powers (referred to as residual powers) to the states. Even though the United States was initially premised on dual federalism, in which federal and state government have different spheres of control, in reality, the nation developed a system of shared federalism, whereby federal and state authorities cooperate on matters that cross levels of government.

The federal government’s powers are further limited by the separation of powers, which provides a system of checks and balances among the executive, legislative, and judicial branches. The equality of the three branches distinguishes the U.S. government from European parliamentary democracies, in which the legislature has supremacy. In the U.S. government, the executive, legislative, and judicial branches all retain powers that, theoretically, allow them to check the authority of the others. For example, the executive has the authority to veto legislative acts; the legislature can override executive vetoes of its legislation; and the judiciary can rule legislative acts and executive orders unconstitutional. In turn, the executive appoints members of the judiciary and the legislature confirms these choices and can impeach members of the judiciary.

Finally, the framers of the Constitution limited the powers of government by outlining the rights of all citizens in the Bill of Rights. The Bill of Rights, which went into effect on December 15, 1791, comprises the first ten amendments to the Constitution. These amendments guarantee such rights as the freedom of speech and religion, the right to bear arms, freedom from unreasonable search and seizure, the right to due process of law, the right to a jury trial, and freedom from cruel and unusual punishment. These constitutional protections, which are binding on both federal and state governments, form the basis of individual political liberty in the United States.

The executive branch, which handles the administrative business of government, is centered on the president, who acts as both the head of state and the head of government. The president serves as commander in chief of the armed forces, negotiates treaties, and—with the advice and consent of the Senate—appoints federal judges, ambassadors, and cabinet officials. The president also has the right to veto bills passed by the legislative branch.

The president serves a four-year term, for a maximum of two elected terms. Citizens elect the president indirectly through the Electoral College system. Each state has an electoral vote that is equal to the total number of representatives and senators from that state (Washington, D.C., also has electoral representation). In each state, the winner of the popular vote for the presidency, which is calculated as a simple majority (more than half), receives that state’s electoral votes.

The president is advised by members of the cabinet, who also head the major departments of government. The cabinet comprises the attorney general and the secretaries of state, treasury, defense, homeland security, interior, agriculture, commerce, labor, health and human services, housing and urban development, transportation, education, energy, and veterans affairs. Cabinet members are appointed by the president with the approval of the Senate; they serve “at the pleasure of the president” and can be dismissed at any time. In addition, presidential aides head a variety of executive offices and councils, such as the Office of Management and Budget, the Council of Economic Advisers, and the National Security Council. These aides hold considerable political power.

The executive branch also includes many independent regulatory agencies, such as the Federal Reserve System and the Security and Exchange Commission; government-owned corporations, such as Amtrak and the U.S. Postal Service; and independent executive agencies, such as the Central Intelligence Agency and the National Aeronautics and Space Administration.

The legislature, called the Congress, is the decision-making branch of government. According to the Constitution, Congress has the power to levy taxes, borrow money, regulate interstate commerce, impeach and convict the president, declare war, discipline its own membership, and determine its rules of procedure. Congress also has oversight of the executive departments.

The Congress is bicameral, consisting of the House of Representatives (lower house) and the Senate (upper house). Legislation may be introduced or amended in either house, although bills related to taxation and expenditures must be initiated in the House of Representatives. A bill must pass both houses and be signed by the president to become law. The president may veto a bill, but that veto can be overridden by a two-thirds majority vote in both houses. In practice, amendments to the Constitution originate in Congress. Proposed amendments must pass both houses by a two-thirds majority and then must be ratified by three-fourths of the state legislatures within a prescribed period (typically seven years).

Each house also has unique functions that are outlined in the Constitution. The House of Representatives has the authority to impeach the president or other public officials by a majority vote. The Senate has important “advice and consent” powers: It must approve treaties negotiated by the president with other governments by a two-thirds vote and has the power to confirm the president’s cabinet, judicial, and diplomatic appointees by simple majority vote.

The House of Representatives consists of 435 members who represent districts apportioned to the states on the basis of population. In this way, more populous states have greater representation in the House than smaller states. Citizens directly elect members of the House to two-year terms by a simple majority system of voting, in which the candidate with the highest number of votes wins the seat. The majority party elects the Speaker of the House, who presides over debate, appoints members to House committees, and controls the chamber’s standing committees, which have the power to amend, delay, or kill legislation. Each committee is chaired by a member of the majority party. The most important committees are those dealing with appropriations, ways and means (financial matters), and rules.

The Senate consists of one hundred members, which are equally distributed among the states (two from each state). Senators serve six-year terms that are staggered so that one-third of the Senate membership is up for election every two years. Senate elections also follow the simple majority system. The leadership structure and committee system in the Senate are similar to those in the House of Representatives. Each party elects a leader to coordinate Senate activities, and the majority party controls the legislative agenda. Senate leaders also play an important role in appointing members of their party to Senate committees, which deliberate and process legislation and exercise oversight of government agencies and departments. The Senate has sixteen standing committees focused on major policy areas.

Finally, the judiciary is the legal branch of the federal government: it is responsible for enforcing the nation’s laws and adjudicating disputes. The U.S. Supreme Court is the ultimate judicial authority. It interprets the Constitution and federal legislation and acts as the final court of appeal. Its nine justices are appointed to life terms by the president with the consent of the Senate. The Court has the authority to determine which appeals it will hear—typically, cases involving disputes among states or matters of constitutional importance.

District courts make up the lower federal court system. Each state has at least one federal district court and one federal judge. Appeals from district courts are brought to one of eleven geographically based circuits of the U.S. Court of Appeals. District court and court of appeals judges are appointed by the president and confirmed by the Senate. In addition, the federal court system maintains special courts to handle property damage suits against the United States, customs rulings, complaints by individual taxpayers, and military cases. Each state has its own local, district, and supreme courts.

The state governments mirror the structure of the federal government. Each state is headed by an elected governor, and each has a legislature, a judiciary, and a state constitution. State governments exercise some powers that overlap with those of the federal government—namely, taxation, the establishment and regulation of courts, and lawmaking and enforcement—but any time a state law conflicts directly with a federal law, the federal law is controlling. States also regulate intrastate commerce, establish local governments, and legislate on matters of public health and safety, as long as their laws do not contradict the Constitution.

Political Parties and Factions

Since the presidential elections of 1860, the Democratic Party and Republican Party have been the primary competitors for executive and legislative control in the U.S. government. Minority parties, like the environmentalist Green Party, and unaffiliated, independent politicians, function primarily to raise public awareness about specific issues and, through their participation in national elections, can alter the balance of power between the primary political parties.

The Democratic Party was founded by Thomas Jefferson in 1792 as a faction of legislators in opposition to the Federalist Party. The party’s primary platform, at its inception, was to promote state autonomy and strict adherence to the constitution. Regarding the major issues of the period—slavery, westward expansion, and economic centralization—Democrats advocated states’ rights and opposed the expansion of federal authority. By the twentieth century, the Democrats had reduced their focus on state autonomy and began to advocate a stronger central government to address the growing economic and class disparities in the labor and urban communities.

The Republican Party, sometimes known as the Grand Old Party or GOP, originated in 1854 to opposed the expansion of slavery into new states and territories. The first president elected under the banner of the Republicans, Abraham Lincoln (1809–1865), brought the party to prominence during the Civil War. The initial Republican platform supported economic centralization, federal regulations regarding slavery and trade, and expansion of the transportation system. By the end of the nineteenth century, the Republican platform had begun to shift toward states’ rights advocacy, conservative social policies, and free-market economic principles.

The Republican Party under President George W. Bush (1946–) took control of the executive branch with the contested 2000 presidential elections, during which Bush won the election in the electoral college but lost the popular vote by a margin of 47.9 to 48.4 percent, marking one of the closest presidential races in U.S. history. President Bush was reelected in 2004, winning approximately 50.7 percent of the popular vote. During the 2003 legislative elections, the Republican Party gained a majority in both houses of Congress and in state governorships—the first time since the 1950s that the Republicans controlled both houses of Congress. Under the Bush administration, the Republican Party focused on enhancing national security through aggressive military expansion and supporting conservative legislation on social issues.

The Republican Party maintained an average approval rating (measured in public opinion polls) of more than 50 percent during the first Bush administration (2000–2004), but this rating declined precipitously during the second Bush administration (2005–2008), falling to a record low of less than 30 percent in 2006. In the 2006 legislative elections, the Democratic Party gained a majority in both houses of Congress. The primary issue leading to the decline in Republican Party support was the 2003 invasion and occupation of Iraq as part of the “war on terror.” In 2007 public opinion polls indicated that less that 25 percent of the population approved of the Republican Party’s policies regarding the Iraqi occupation.

Major Events

Even though the fundamental structure of the current U.S. government has remained unchanged since the founding of the republic, the scope and powers of government have evolved over time. Significant changes occurred during two periods of U.S. history: the Civil War and the New Deal era of the 1930s and 1940s.

The Civil War spurred important constitutional changes that recast Americans’ relationship with the federal government. Three constitutional amendments were passed in the aftermath of the Civil War: the Thirteenth Amendment, which banned slavery; the Fourteenth Amendment, which extended federal legal protections; and the Fifteenth Amendment, which abolished racial restrictions on voting. Before the Civil War, most Americans had little interaction with the federal government outside of the postal service. The passage of the Fourteenth Amendment prevented the states from denying freed slaves “life, liberty, or property, without due process of law” and guaranteed them “the equal protection of its laws.”

In the mid-twentieth century these amendments were employed for purposes beyond their original intent. Broad interpretation of the due process clause of the Constitution permitted the Supreme Court to extend the protections guaranteed in the Bill of Rights to the states. Furthermore, the Court applied the equal protection clause to declare racial segregation in public schools unconstitutional and later to challenge zoning laws, the drawing of congressional voting districts, and discrimination on the basis of sex.

During the twentieth century the Great Depression (1929–1938) and U.S. involvement in World War II (1939–1945) prompted a massive expansion of the U.S. federal government. President Franklin D. Roosevelt (1882–1945) promised to rescue the United States with a “New Deal” that offered farming subsidies, public works projects, rural electrification, price and wage controls, and old-age pensions and created federal agencies to handle labor conflicts, guarantee bank deposits, monitor stock transactions, and dispense welfare funds.

Roosevelt’s policies also set a precedent for federal regulation of the economy and laid the groundwork for a large national security administration. Between 1941 and 1945, for example, the U.S. military expanded in size and sophistication as the federal government spent more than $300 billion on everything from increased staffing to atomic bombs. The threat of communism during the Cold War—a period of increased tensions between the United States, the Soviet Union, and their allies—added to the size of the defense establishment: The Atomic Energy Commission, the National Security Council, the Central Intelligence Agency, a unified Department of Defense, and the National Security Agency were all created by congressional act or executive order between 1946 and 1952.

Twenty-First Century

U.S. politics in the twenty-first century can be characterized as highly partisan,with little cooperation between the Democratic and Republican parties. Conflict between the parties has centered largely on U.S. foreign relations in the Middle East, the war in Iraq, the best methods of ensuring homeland security, social issues such as abortion and gay rights, and the development of new energy policies to meet the country’s rising demand for oil.

Amar, Akhil Reed. America’s Constitution: A Biography . New York: Random House, 2005.

Hershey, Marjorie Randon. Party Politics in America . 12th ed. New York: Pearson Longman, 2007.

Wiebe, Robert H. The Search for Order, 1877–1920 . Westport, Conn.: Greenwood Press, 1980.

Wilentz, Sean. The Rise of American Democracy: Jefferson to Lincoln . New York: Norton, 2005.

Wood, Gordon S. The Creation of the American Republic, 1776–1787 . Chapel Hill: University of North Carolina Press, 1998.

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