Gellert Grindelwald

In 1926, the students of Hogwarts were sent home early due to a threat from the dark wizard Gellert Grindelwald. Steps were taken to increase security at the school, but when the Daily Prophet reported the danger, the choice was made to send them home. The School’s permanent closure was considered during both openings of the Chamber of Secrets, but it didn’t end up being shut down either time. Then again, when Dumbledore was murdered, several of the teachers felt that the school should be closed, but the Ministry of Magic’s takeover by Death Eaters forced it to remain open that year under their rule.