Complex sentence: When Heuton and Falacci brought back Oswald for "Democracy", they added the characterization of Oswald as a Canadian possibly because, during the filming of "Hardball", they learned of Baruchel's tattoo of the Canadian maple leaf on his chest.
Split into simpler sentences: When Heuton and Falacci brought back Oswald for "Democracy", they added the characterization of Oswald as a Canadian. During the filming of "Hardball", they learned that Baruchel's tattoo of the Canadian maple leaf on his chest.