The eruption of Krakatoa in Indonesia is one of the largest eruptions in recorded history. It is said that the shock wave from the explosive blast went around the earth three times. Most of the people killed by the eruption, over 36,000 people, were killed by the great tsunami that swept through the Indonesian archipelago. Sulfuric acid and ash from the eruption was blown all the way up into the stratosphere, where it stayed for several years before dispersing. This caused very beautiful red sunsets that are depicted in many paintings of the time and caused a cooling in global temperature that lasted several years. You can read a description of it from the Australian Bureau of Meteorology here. An infographic from the National Weather Service on the tsunami from Krakatoa is shown below.
