On June 29, 1816, Indiana’s first state constitution was completed, preparatory to its submission to Congress in petition for statehood. (The Indiana Territory was officially granted statehood by Congress in November; statehood became official December 11 of the same year.)
The 1816 constitution was later thrown out, replaced by one written in 1851 (which still stands)… but Indiana would not have become a state without the government established by the first one, so we’ll give it some credit.
So, happy 196th constitutional-establishment anniversary, Hoosiers!