1634    The first settlers arrive in Maryland.

1738    A treaty between Pennsylvania and Maryland ends the Conojocular War with settlement of a boundary dispute and exchange of prisoners.

1767    Mason-Dixon line, survey separating Maryland from Pennsylvania is completed.

1788    Maryland becomes the seventh state to ratify the Constitution of the United States.

1838    Dressed in a sailor's uniform and carrying identification papers provided by a Free Black seaman, future abolitionist Frederick Douglass boards a train in Maryland on his way to freedom from slavery.

1844    Samuel Morse sends the message "What hath God wrought" (a Bible quotation, Numbers 23:23) from the Old Supreme Court Chamber in the United States Capitol to his assistant, Alfred Vail, in Baltimore, Maryland to inaugurate the first telegraph line.

1861    American Civil War: Maryland's House of Delegates votes not to secede from the Union.

1877    After rioting by Baltimore and Ohio Railroad workers and the deaths of nine rail workers at the hands of the Maryland militia, workers in Pittsburgh, Pennsylvania stage a sympathy strike that is met with an assault by the state militia.

1963    Pan Am Flight 214, a Boeing 707, is struck by positive lightning and crashes near Elkton, Maryland, United States, killing all 81 people on board.

1973    U.S. Vice President Spiro Agnew appears on television to denounce accusations he had taken kickbacks while governor of Maryland.

1978    Camp David Accords: Menachem Begin and Anwar Sadat begin peace process at Camp David, Maryland.

1996    The body of former CIA director William Colby is found washed up on a riverbank in southern Maryland, eight days after he disappeared.