  jay county is a county located in the u.s. state of indiana. as of 2010, the population was 21,253. the county seat is portland. ==history== jay county was formed in 1836. it is the only county in the united states named for john jay, co-author of the federalist papers, secretary of foreign affairs under the articles of confederation, and first chief justice of the united states. john jay died in 1829. ==geography== according to the 2010 census, the county has a total area of , of which  (or 99.95%) is land and  (or 0.05%) is water. ===cities and towns=== *bryant *pennville *portland *redkey *salamonia *dunkirk ===townships=== *bearcreek *greene *jackson *jefferson *knox *madison *[[noble township, jay cou
1836_establishments_in_Indiana Indiana_counties Jay_County,_Indiana John_Jay Law_enforcement_agencies_of_Indiana Populated_places_established_in_1836