Argentina did so with the signing of the Argentine Constitution of 1853. Peru abolished slavery in 1854. Colombia abolished slavery in 1851. Slavery was abolished in Uruguay during the Guerra Grande, by both the government of Fructuoso Rivera and the government in exile of Manuel Oribe. Canada Throughout the growth of slavery in the American South, Nova Scotia became a destination for black refugees leaving Southern Colonies and United States. While many blacks who arrived in Nova Scotia during the American Revolution were free, others were not. Black slaves also arrived in Nova Scotia as the property of White American Loyalists. In 1772, prior to the American Revolution, Britain determined that slavery could not exist in the British Isles followed by the Knight v. Wedderburn decision in Scotland in 1778. This decision, in turn, influenced the colony of Nova Scotia. In 1788, abolitionist James Drummond MacGregor from Pictou published the first anti-slavery literature in Canada and began purchasing slaves' freedom and chastising his colleagues in the Presbyterian church who owned slaves. In 1790 John Burbidge freed his slaves. Led by Richard John Uniacke, in 1787, 1789 and again on 11 January 1808, the Nova Scotian legislature refused to legalize slavery. Two chief justices, Thomas Andrew Lumisden Strange (1790–1796) and Sampson Salter Blowers (1797–1832) were instrumental in freeing slaves from their owners in Nova Scotia. They were held in high regard in the colony. By the end of the War of 1812 and the arrival of the Black Refugees, there were few slaves left in Nova Scotia. The Slave Trade Act outlawed the slave trade in the British Empire in 1807 and the Slavery Abolition Act of 1833 outlawed slavery altogether. With slaves escaping to New York and New England, legislation for gradual emancipation was passed in Upper Canada (1793) and Lower Canada (1803). In Upper Canada, the Act Against Slavery of 1793 was passed by the Assembly under the auspices of John Graves Simcoe. It was the first legislation against slavery in the British Empire. Under its provisions no new slaves could be imported, slaves already in the province would remain enslaved until death, and children born to female slaves would be slaves but must be freed at the age of 25. The last slaves in Canada gained their freedom when slavery was abolished in the entire British Empire by the Slavery Abolition Act of 1833. United States In his