Complex sentence: Frank McErlane (1894-8 October 1932) was a Prohibition-era gangster who led the Saltis-McErlane Gang, allied with the Johnny Torrio-Al Capone Gang, against rival bootleggers the Southside O'Donnell Brothers.
Split into simpler sentences: Frank McErlane (1894-8 October 1932) was a Prohibition-era gangster. He led the Saltis-McErlane Gang, allied with the Johnny Torrio-Al Capone Gang, against rival bootleggers, the Southside O'Donnell Brothers.