The latest in a recent wave of films on past and present troubles in Central Africa, the new documentary King Leopold’s Ghost sets itself apart with its historical scope. Based on a book by American journalist Adam Hochschild, King Leopold’s Ghost devotes its first half to the era between 1880 and World War I, during which unknown millions of Congolese died as a result of the forced production of rubber. Sleeker and more ambitious than the 2003 BBC-produced Congo: White King, Red Rubber, Black Death, which focused more narrowly on long-suppressed Belgian atrocities of that era, King Leopold’s Ghost traces the living legacy of colonialism, pausing to consider the 1961 assassination of Patrice Lumumba and the subsequent Mobutu years (there’s a damming video clip of George H.W. Bush introducing the dictator as “one of our most valued friends”), and linking the country’s recent civil wars to continuing economic exploitation. Overstuffed with information on everything from the importance of coltan mining to the minutiae of recent U.N. investigations, the last half-hour should be expanded into its own movie.