Denmark was the first European country to ban the import of slaves to its colonies in 1803, four years before Britain . The USA made the slave trade illegal in 1808 , but laws to ban the owning of slaves were not passed until 1865.
This picture called 'George Washington working as a farmer at mount Vernon' was created in 1851 by Junius Brutus Stearns. It gives us a sentimentalised view of slaves working at Mount Vernon in the USA.