Sentence:  Moreover, once retrieved, suppressed events, confrontational episodes, submerged political upheavals, abortive uprising offer symbolic density or enrichment to current circumstances. They enlarge the retina of the political eye. How to transform the <WSD>unhistory</WSD> of the negativized, to make the anonymes impinge on history, is one way to put the matter. 
Meaning of the word marked with <WSD> tags:  The suppressed history of controversial events.