U.S. states in the context of "Eastern Time Zone"

The East Coast of the United States, also known as the Eastern Seaboard, the Atlantic Coast, and the Atlantic Seaboard, is the region encompassing the coastline where the Eastern United States meets the Atlantic Ocean; it has always played a major socioeconomic role in the development of the United States.

The region is generally understood to include the U.S. states that border the Atlantic Ocean: Connecticut, Delaware, Florida, Georgia, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, North Carolina, Rhode Island, South Carolina, and Virginia, as well as some landlocked states (Pennsylvania, Vermont, West Virginia, and the district of Washington, D.C.).

The Illinois Country (French: Pays des Illinois [pɛ.i dez‿i.li.nwa]; lit. 'land of the Illinois people'; Spanish: País de los ilinueses), also referred to as Upper Louisiana (French: Haute-Louisiane [ot.lwi.zjan]; Spanish: Alta Luisiana), was a vast region of New France claimed in the 1600s that later fell under Spanish and British control before becoming what is now part of the Midwestern United States. While the area claimed included the entire Upper Mississippi River watershed, French colonial settlement was concentrated along the Mississippi and Illinois Rivers in what is now the U.S. states of Illinois and Missouri, with outposts on the Wabash River in Indiana. Explored in 1673 from Green Bay to the Arkansas River by the Canadien expedition of Louis Jolliet and Jacques Marquette, the area was claimed by France. It was settled primarily from the Pays d'en Haut in the context of the fur trade, and in the establishment of missions from Canada by French Catholic religious orders. Over time, the fur trade took some French to the far reaches of the Rocky Mountains, especially along the branches of the broad Missouri River valley. The "Illinois" in the territory's name is a reference to the Illinois Confederation, a group of related Algonquian native peoples.

The Illinois Country was governed from the French province of Canada until 1717 when, by order of King Louis XV, it was annexed to the French province of Louisiana, becoming known as "Upper Louisiana". By the mid-18th century, major settlements included Cahokia, Kaskaskia, Chartres, Saint Philippe, and Prairie du Rocher, all on the east side of the Mississippi in present-day Illinois; and Ste. Genevieve across the river in what is now Missouri, as well as Fort Vincennes in what is now Indiana.

From the late 18th century to the 1860s, various states of the United States allowed the enslavement of human beings, most of whom had been transported from Africa during the Atlantic slave trade or were descendants of people who had. The institution of chattel slavery was established in North America in the 16th century under Spanish, British, French, and Dutch colonization.

After the United States was founded in 1776, the country split into slave states (states permitting slavery) and free states (states prohibiting slavery). Slavery became concentrated in the Southern United States. The Act Prohibiting Importation of Slaves banned the Atlantic slave trade starting in 1808, but not the domestic slave trade or slavery itself. Slavery was finally ended throughout the entire country after the American Civil War (1861–1865), in which the U.S. government defeated a confederation of rebelling slave states that attempted to secede from the U.S. During the war, U.S. president Abraham Lincoln issued the Emancipation Proclamation, which ordered the liberation of all slaves in rebelling states. In December 1865, the Thirteenth Amendment to the U.S. Constitution was ratified, abolishing chattel slavery nationwide. Native American slave ownership also persisted until 1866, when the federal government negotiated new treaties with the "Five Civilized Tribes" in which they agreed to end slavery. Some argue slavery continues to exist because the Thirteenth Amendment contains an exception for people convicted of a crime.

The Mason–Dixon line, sometimes referred to as Mason and Dixon's Line, is a demarcation line separating four U.S. states: Pennsylvania, Maryland, Delaware and West Virginia. It was surveyed between 1763 and 1767 by English surveyors and astronomers Charles Mason and Jeremiah Dixon as part of the resolution to Cresap's War, a border conflict involving Maryland, Pennsylvania, and Delaware (then a part of Pennsylvania) in the colonial United States.

The largest portion of the Mason–Dixon line, along the southern Pennsylvanian border, later became informally known as the boundary between the Southern slave states and Northern free states. This usage came to prominence during the debate around the Missouri Compromise of 1820, when drawing boundaries between slave and free territory, and resurfaced during the American Civil War, with border states also coming into play. The Confederate States of America claimed the Virginian (now West Virginia) portion of the line as part of its northern border, although it never exercised meaningful control that far north – especially after West Virginia separated from Virginia and joined the Union as a separate state in 1863. It is still used today in the figurative sense of a line that separates the Northeast and South regionally, politically, and socially (see Dixie).

The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, or the Eisenhower Interstate System, is a network of controlled-access highways that forms part of the National Highway System in the United States. The system extends throughout the contiguous United States and has routes in Hawaii, Alaska, and Puerto Rico.

In the 20th century, the United States Congress began funding roadways through the Federal Aid Road Act of 1916, and started an effort to construct a national road grid with the passage of the Federal Aid Highway Act of 1921. In 1926, the United States Numbered Highway System was established, creating the first national road numbering system for cross-country travel. The roads were funded and maintained by U.S. states, and there were few national standards for road design. United States Numbered Highways ranged from two-lane country roads to multi-lane freeways. After Dwight D. Eisenhower became president in 1953, his administration developed a proposal for an interstate highway system, eventually resulting in the enactment of the Federal-Aid Highway Act of 1956.

Women's suffrage, or the right of women to vote, was established in the United States over the course of the late 19th and early 20th centuries, first in various states and localities, then nationally in 1920 with the ratification of the 19th Amendment to the United States Constitution.

The demand for women's suffrage began to gather strength in the 1840s, emerging from the broader movement for women's rights. In 1848, the Seneca Falls Convention, the first women's rights convention, passed a resolution in favor of women's suffrage despite opposition from some of its organizers, who believed the idea was too extreme. By the time of the first National Women's Rights Convention in 1850, however, suffrage was becoming an increasingly important aspect of the movement's activities.

The rule of capture or law of capture, part of English common law and adopted by a number of U.S. states, establishes a rule of non-liability for captured natural resources including groundwater, oil, gas, and game animals. The general rule is that the first person to "capture" such a resource owns that resource. For example, landowners who extract or "capture" groundwater, oil, or gas from a well that bottoms within the subsurface of their land acquire absolute ownership of the substance even if it is drained from the subsurface of another's land. The landowner who captures the substance owes no duty of care to other landowners. For example, a water well owner may dry up wells owned by adjacent landowners without fear of liability unless the groundwater was withdrawn for malicious purposes, the groundwater was not put to a beneficial use without waste, or (in Texas) "such conduct is a proximate cause of the subsidence of the land of others." An exception to the rule of capture is that a person who drills for groundwater, oil, or gas may not extract the substance from a well that bottoms within the subsurface estate of another by drilling on a slant.

The Smithsonian Institution (/smɪθˈsoʊniən/ smith-SOH-nee-ən; or simply the Smithsonian) is a group of museums, education and research centers, created by the United States federal government "for the increase and diffusion of knowledge". Founded on August 10, 1846, it operates as a trust instrumentality and is not formally a part of any of the three branches of the federal government. The institution is named after its founding donor, British scientist James Smithson. It was originally organized as the United States National Museum, but that name ceased to exist administratively in 1967.

The Smithsonian Institution has historical holdings of over 157 million items, 21 museums, 21 libraries, 14 education and research centers, a zoo, and historical and architectural landmarks, mostly located in Washington, D.C. Additional facilities are located in Maryland, New York, and Virginia. More than 200 institutions and museums in 47 states, Puerto Rico, and Panama are Smithsonian Affiliates. Institution publications include Smithsonian and Air & Space magazines.