Shakespeare's Fulvia：Short, boring & in sheer contrast with the exotic Cleopatra; her marriage with Antony was negotiated with Antony by the patriarchal figures in her family
Jonson's Fulvia: Ambitious, cunning, manipulative; a proper politician; somehow nobler than the whole Roman Senate combined as a high-level whore
The real Fulvia in history: closer to Jonson's characterisation