Ubisoft has revealed that Assassin's Creed II sold "nearly nine million units" during its last financial year, which ended on 31st March 2010.
The company also said that the next instalment in the series, Assassin's Creed: Brotherhood, will be preceded by a multiplayer beta ahead of its autumn release.
More details on that should be made available at E3 in June. For now we know that multiplayer sees players control the Templars.
When Assassin's Creed II was officially announced last April, Ubisoft said its predecessor had sold eight million units, suggesting that the second instalment has now outperformed it.
The publisher has previously said the series was a trilogy, but Brotherhood - which follows ACII protagonist Ezio Auditore - has been described as an extra episode rather than a full release.
Company boss Yves Guillemot's stated intention for Ubisoft to ship new instalments in its major franchises more frequently, and for them to include multiplayer.