St. John the Baptist Parish (SJBP, ) is a parish located in the U.S. state of Louisiana. As of the 2010 census, the population was 45,924. The parish seat is Edgard, an unincorporated area, and the largest city is LaPlace, also unincorporated. St. John the Baptist Parish was established in 1807 as one of the original 19 parishes of the Territory of Orleans, which became the state of Louisiana.