the rebel Confederate States. As a Union border state, Maryland was not included in President Lincoln's 1863 Emancipation Proclamation, which declared all slaves in Southern Confederate states to be free. The following year, Maryland held a constitutional convention. A new state constitution was passed on November 1, 1864, and Article 24 prohibited the practice of slavery. The right to vote was extended to non-white males in the Maryland Constitution of 1867, which remains in effect today. (The vote was extended to women of all races in 1920 by ratification of a national constitutional amendment.) Beginnings Tobacco From the beginning, tobacco was the dominant cash crop in Maryland. Such was the importance of tobacco that, in the absence of sufficient silver coins, it served as the chief medium of exchange. John Ogilby wrote in his 1670 book America: Being an Accurate Description of the New World: "The general way of traffick and commerce there is chiefly by Barter, or exchange of one commodity for another". Since land was plentiful, and the demand for tobacco was growing, labor tended to be in short supply, especially at harvest time. The first Africans to be brought to English North America landed in Virginia in 1619, rescued by the Dutch from a Portuguese slave ship. These individuals appear to have been treated as indentured servants. A significant number of Africans after them also gained freedom through fulfilling a work contract or for converting to Christianity. Some successful free people of color, such as Anthony Johnson, prospered enough to acquire slaves or indentured servants. This evidence suggests that racial attitudes were much more flexible in the colonies in the 17th century than they later became, when slavery was hardened as a racial caste. Import of enslaved Africans The first documented Africans were brought to Maryland in 1642, as 13 slaves at St. Mary's City, the first English settlement in the Province. Earlier, in 1638, the Maryland General Assembly had considered, but not enacted, two bills referring to slaves and proposing excepting them from rights shared by Christian freemen and indentured servants: An Act for the Liberties of the People and An Act Limiting the Times of Servants. The legal status of Africans initially remained undefined; since they were not English subjects, they were considered foreigners. Colonial courts tended to rule that any person who accepted Christian baptism should be freed. In order to protect the property