Papadiamantopoulos was an upper-class resident of Patras before the Greek revolution broke out in 1821.
Papadiamantopoulos sold his entire estate during the revolution started and ran a weapons trade from Italy.
In March 1822, he was a fortress chief of the battlefield in Patras and participated in the surrender of the castle of Nafplio by the Ottomans.
Papadiamantopoulos participated also in the naval battles of Hydra and Spetses and also of Elis.
He was made president of the tri-member with commission power fallow Greece.