And Ira Berlin, the extraordinary historian who chronicled the history of U.S. slavery, has died at the age of 77. Berlin studied millions of documents in his lifetime to tell the stories of African Americans fighting for emancipation. His books included “Generations of Captivity,” “Slaves Without Masters” and “Many Thousands Gone: The First Two Centuries of Slavery in North America.” He once said of his work, “One does not get over history, one just has to come to terms with it.”