In 1816, an eruption from Mount Tambora in Indonesia caused unprecedented global climate change, leading to a year without a summer. The eruption ejected massive amounts of sulphur into the atmosphere, forming sulphate aerosols that reflected sunlight and prevented it from reaching the Earth’s surface. This resulted in a year of abnormally cold temperatures, heavy snowfall, and devastating crop failures worldwide. The effects were particularly severe in Europe and North America, where widespread hunger, riots, and disease outbreaks occurred. The event highlights the far-reaching consequences of volcanic eruptions and their potential to disrupt human societies.