With the death of Franz-Ferdinand of Austria, the complex web of alliances of Europe began unraveling into factions that quickly polarized into two world alliances pitted against one another. Siding with Austro-Hungary were Germany, Bulgaria and the Ottoman Empire. The souring of Confederate relations with Britain had lead it into the arms of the Central Powers. The war was bloody, if not the bloodiest in human history, with the infrastructure on both continents disastrously weakened.