The Fukushima Daiichi Nuclear Disaster was a catastrophic nuclear accident at the Fukushima Daiichi Nuclear Power Plant in Ōkuma, Fukushima Prefecture, initiated primarily by the tsunami following the Tōhoku earthquake on March 11, 2011. It resulted in the release of radioactive materials, leading to widespread evacuations, long-term environmental damage, and a reevaluation of nuclear energy policies worldwide.