This is the system by which the main institutions of a nation's government are arranged and kept in place. it may be written down (as in the united states) or it may be unwritten (as in great britain).

Direct democracy is the system

its is constitution

the lachish letters were written by hoshaiah, a military officer stationed possibly in mareshah,   and sent to yaush, possibly the commanding officer at lachish.

the series of letters were written in carbon ink in ancient hebrew on clay ostraca, shortly before lachish fell to the babylonian army of king nebuchadnezzar in 588/6 bc during the reign of zedekiah, king of judah.