Moses Brown, founder of Brown Square and one of Newburyport's wealthiest residents, became wealthy from New England's Triangle Trade, the economic engine that drove much of the slave trade in the 18th and 19th centuries. Although he refused to become directly involved in the slave trade, the foundation of his wealth was the trade and importation of slave-produced sugar and molasses from the West Indies. He sold the imported sugar and molasses and established a rum distillery at the foot of Green Street in an area still known as Brown's Wharf. In 1802, he laid out Brown Square as a tree-lined public open space and made many philanthropic gifts to the community. His life and the history of Brown Square reflect New England's complex relationship with slavery, including the Triangle Trade and, generations later, the Abolition Movement. Brown and many other Newburyport merchants were deeply involved in the sugar and rum trade that fueled the enslavement of millions of Africans. Much of the rum distilled in New England was consumed in North America, and many trade goods were exchanged for slaves on the West African coast, but most New England rum was shipped to Africa and exchanged by traders for more slaves. Enslaved Africans were then transported across the Atlantic to the New World, where the vast majority were sent to labor in Caribbean sugar plantations, producing more sugar and molasses to continue the cycle. During much of Brown's life, cheap rum was New England's chief manufactured product, and rum exports were the main foundation of the regional economy. Newburyport had about 10 rum distilleries in 1790, and Massachusetts had about 60 at the height of the industry. By the end of the 1700s, sugar, molasses, and rum were so closely tied to slavery that some abolitionists urged people to stop using sugar.