{"gt_parse": {"text_sequence": "ereafter. Depopulation resul ting from the plague was thus almost cert ainly a major factor in t he success of early Ottoman expansi on into the Balkans, and contribu ted to th e weaken ing of the By zantine Emp ire and the depopulati on of Const antinople.Go vernme nt.During this ea rly pe riod be fore the O ttomans were able to esta blish a centr alized sy stem of governme nt in the middl e of the fi fteenth centur y the rulers ' powers"}}