What events led napoleon lll to declare war on prussia?

Napoleon III declared war on Prussia in 1870 primarily due to rising tensions over the candidacy of a Hohenzollern prince to the Spanish throne, which France opposed. Additionally, the diplomatic manipulation by Otto Von Bismarck, who released the Ems Dispatch, inflamed French public opinion and made war seem inevitable. Feeling pressured and seeking to assert French dominance, Napoleon III ultimately decided to go to war, believing it would unify the French people and restore his regime's prestige.