1400 - The Lenni Lenape, Native Americans of the Algonkians, settle along the Delaware.
1600 - Minquas, from the Susquehanna River Valley, began to attack the villages of the Lenni Lenape.
1609 - Henry Hudson, an Englishman sailing for the Dutch East India Company, discovers Delaware Bay and River.
1610 - Captain Samuel Argall, an English sea captain, names the bay and river after Lord De La Warr, the governor of Virginia.
1631 - Dutch colonists settle at Zwaanendael (site of present-day Lewes).
1632 - Settlement at Zwaanendael is destroyed and all colonists killed in dispute with Native Americans.
1638 - Peter Minuet leads a group of Swedes to the Delaware and establishes Fort Christina (now Wilmington), the first permanent settlement on the Delaware and the beginnings of the New Sweden Colony.
1639 - The first African on the Delaware, Black Anthony, is brought from the Caribbean to Fort Christina.
1640 - The first Lutheran minister in America, the Reverend Reorus Torkillus, arrives at Fort Christina.
1643 - Johan Printz becomes governor of the New Sweden Colony.
1651 - Peter Stuyvesant, Dutch governor of New Netherland, builds Fort Casimir (now New Castle) just a few miles south of Fort Christina on the Delaware.
1654 - The Swedes capture Fort Casimir and rename it Fort Trinity.
1659 - Lewes is founded.
1655 - The Dutch defeat the Swedes on the Delaware, ending the New Sweden Colony. Delaware becomes a part of New Netherland.
1664 - Expedition led by Colonel Sir Richard Nicolls, one of four Commissioners appointed by the Crown to carry out military acquisition of the Dutch territories in America. Nicolls selected Sir Robert Carr to subdue the Dutch on the South (Delaware) River. Sir Robert Carr drives the Dutch off the Delaware and claims the land for James, Duke of York. Delaware becomes an English colony.
1673 - The Dutch regain control of the Delaware.
1674 - The English regain the Delaware
1681 - William Penn was granted land from England, that included Delaware, and established the colony of Pennsylvania.
1682 - The Duke of York transfers control of the Delaware Colony to English Quaker William Penn.
1698 - Holy Trinity, Old Swedes Church, is built in Wilmington.
1698-1700 - Pirates including Captain Kidd sail along the Delaware.
1704 - Delaware's first assembly of the Three Lower Counties Upon Delaware, separate from Pennsylvania, meets at New Castle.
1717 - Town of Dover laid out.
1731 - Thomas Willing founds Willingtown.
1739 - Willingtown receives royal charter and is renamed Wilmington.
1742 - Oliver Canby builds flour mill on Brandywine River at Wilmington, beginning large commercial flour milling industry.
1760 - 35,000 people lived in the Delaware region.
1761 - James Adams sets up first printing press in Delaware at Wilmington.
1763 - The French and Indian War ends in 1763 and Great Britain gains controls of all lands previously held by France. England pays for the war by increasing taxes on its American Colonies. Restrictions on the colonists eventually lead to a fight for independence from the crown.
1764 - Charles Mason and Jeremiah Dixon survey Delaware's western boundary.
1765 - Caesar Rodney and Thomas McKean represent Delaware at the Stamp Act Congress.
1767-68 - John Dickinson writes Letters from a Farmer in Pennsylvania, an influential protest against British policies towards the colonies.
1774 - Caesar Rodney, Thomas McKean, and George Read represent Delaware at the First Continental Congress.
1775 - Revolutionary War began
1779 - Delaware Assembly ratifies Articles of Confederation.
1784 - Thomas Coke and Francis Asbury meet at Barratt's Chapel in Frederica, establishing the Methodist Church as a separate denomination in the US
1785 - Oliver Evans builds prototype automatic flour mill in Newport.
Delaware Gazette, state's first newspaper, begins publication.
1786 - Delaware is one of 5 states to send delegates to Annapolis Convention, which hoped to revise the Articles of Confederation.
1787 - Dec. 7 - Delaware ratified the United States Constitution and became the 1st state in the Union.
1788-89 - Abolition societies established in Dover and Wilmington.
1791 - The county seat of Sussex County is moved from Lewes to Georgetown.
1792 - Delaware adopts second state constitution and changed its name to the State of Delaware.
1795 - Bank of Delaware, the state's first bank, founded in Wilmington.
1802 - Frenchman Éleuthére Irénée du Pont founded a gunpowder mill near Wilmington.
duPont de Nemours begins manufacturing gunpowder along the Brandywine River near Wilmington.
1805 - First Methodist camp meeting held near Smyrna.
1807 - Caesar A. Rodney named Attorney General of the United States by President Thomas Jefferson.
1808 - Newport and Gap Turnpike becomes first toll road in Delaware.
1812-13 - Peter Spencer founds the African Union Methodist Protestant Church. AUMP is the first denomination in the nation controlled entirely by African-Americans.
1818 - Construction begins on the mile-long Delaware Breakwater, completed in 1835.
1828 - Steamboat line opens between Philadelphia and New Castle.
1838 - Philadelphia, Wilmington and Baltimore Railroad opens.
1844 - The Bangor, America's first iron-hulled propeller steamship, launched in Wilmington.
1847 - Delaware Senate considers an act to abolish slavery. The act is defeated by one vote.
1849 - John M. Clayton appointed Secretary of State of the United States.
1852 - Delaware Railroad Company organized.
1855 - State-wide prohibition law enacted; repealed, 1857.
1856 - Delaware Railroad completed to Seaford; to Delmar in 1859.
1862 - Delaware legislature rejects President Lincoln's offer to buy its slaves.
1861-65 - Delaware remained in the Union during the Civil War (1861-1865). More than 12,000 Delawareans fought for the North and a few hundred fought for the South. At the end of the war, all slaves were freed.
1865 - Thirteenth Amendment to the US Constitution abolishes slavery. The Delaware legislature votes against the amendment.
1867 - Howard High School, Delaware's first high school for African-Americans, established.
1868 - The 14th Amendment of the US Constitution guarantees equal protection for all races under the law. The Delaware legislature votes against the amendment.
1869 - First woman suffrage convention in Delaware
1872 - Coeducation introduced at Delaware College, discontinued in 1885.
1875 -State legislature creates separate schools with separate funding for white children and African American children.
1876 - Indian River Lifesaving Station is built, the nation's oldest station still on its original site.
1878 - First telephone line installed in Wilmington.
1882 - First electric street lights installed in Wilmington.
1883-86 - Baltimore and Ohio Railroad extends through Delaware.
1885 - Thomas F. Bayard appointed Secretary of State of the United States.
1887 - Volunteer, a steel-hulled racing yacht, built in Wilmington, defeats Thistle to win America's Cup.
1888 - Electric street cars begin to replace horse cars in Wilmington.
1889 - Law passes prohibiting punishment of women at whipping post or pillory.
1899 - The Delaware Corporation Law is passed. In time this law will make it easier for businesses to incorporate in Delaware than in other states.
1901 - Legislature ratifies 13th, 14th, and 15th Amendments to the United States Constitution.
1905 - Delaware becomes last state to abolish use of the pillory.
1911-24 - T. Coleman du Pont builds a highway running the length of the state and gives to State of Delaware.
1911 - Upton Sinclair and Scott Nearing, along with others, arrested at Arden for playing games on Sunday.
1914 - Women's College opens in Newark.
1917-18 - Nearly 10,000 Delawareans serve in World War I.
1920 - Woman suffrage amendment narrowly fails adoption in legislature.
1921 - Construction begins on Wilmington Marine Terminal, completed 1923.
1923 - Cecile Steele begins Delaware's broiler chicken industry.
1926 - Cape Henlopen Lighthouse collapses.
1929 - Louis L. Redding becomes first African-American lawyer in state.
1934 - United States Supreme Court confirms Delaware's claim to control Delaware River.
1938 - Tercentenary Celebration of landing of Swedes in Wilmington.
1939 - DuPont Company opens first nylon plant in Seaford and nylon stockings exhibits at World Fairs in San Francisco and New York.
1941-45 - 30,000 Delaware men and women serve in armed forces in World War II.
1942 - Fort Miles created between Lewes and Rehoboth Beach.
Major air bases created at New Castle and Dover.
1945 - Women's College merges with University of Delaware.
1949 - First annual Delmarva Chicken Festival held.
1950 - Delaware Court of Chancery orders University of Delaware to end segregation.
1951 - Delaware Memorial Bridge opens first span linking Delaware to New Jersey.
1964 - Cape May- Lewes Ferry begins operation.
1969 - Richard Petty wins the first NASCAR-sanctioned race at Dover Downs.
1971 - The Delaware Coastal Zone Act prohibits construction of industrial plants on coastal areas.
1975 - William "Judy" Johnson, a former Negro League baseball player, becomes state's first player elected to the National Baseball Hall of Fame.
1978 - Daniel Nathans wins the Nobel Prize in Medicine for his work with molecular hormones.
1981 - The Financial Center Development Act passes, encouraging out-of-state banks to move headquarters to Delaware.
1984 - S.B. Woo elected lieutenant governor, becoming the highest-ranking Asian-American official in the United States.
1999 - Jacqueline Jones, a native of Christiana, wins prestigious MacArthur Genius Award.
2000 - Ruth Ann Minner elected Delaware's first woman governor.
Source: The Historical Society of Delaware