Jacob Marley was born in 1785. He was a banker, and an usurious moneylender. He worked at a counting house, with his business partner, Ebenezer Scrooge. Marley was disgusted by the poor, and praised workhouses.
He died on 24 December, 1836.
Ebenezer Scrooge and him were very similar. At about 9pm, on Christmas Eve, in 1843, Jacob Marley's ghost haunted Scrooge's house, telling him to change his ways, and become a good person, or else he would end up like HIM! You see, Marley's ghost was transparent, glowing green, and was wearing lots of chains, that weighed him down. Each and every individual heavy link that made up his chains represented a sin he had done, while he was alive and had not regretted.
Because Scrooge was still reluctant to change his ways, Marley told him that he would subsequently be visited by three other different ghosts, that night, who would also try and convince him to change his ways. And then Marley's ghost left.