Jan Roothaan, Dutch priest, 21st Superior-General of the Society of Jesus (d. 1853) Jan Philipp Roothaan (23 November 1785 – 8 May 1853) was a Dutch Jesuit, elected twenty-first Superior-General of the Society of Jesus.
Invading Siamese forces attempt to exploit the political chaos in Vietnam, but are ambushed and annihilated at the Mekong river by the Tây Sơn in the Battle of Rạch Gầm-Xoài Mút.