The Senate was created by the 1997 Organic Law. Before the promulgation of that document, the Ziu consisted only of a single house (now termed the "lower house"), the Cosa. Therefore, the first Senate was the Senate for the 23rd Cosa.
Ever since changes ratified after the 35th Cosa, the King has been Organically barred from holding a place in the Senate, and indeed from entering the Senate chamber unless summoned there to provide testimony to a Senate commission. The consort of the King, and any regent during his or her regency also is forbidden from holding a seat in the Senate. Furthermore, no Senator may hold seats in the Cosa.
The powers of the Senate are equal to those of the Cosa, except that no bill appropriating revenue may have a Senator as its primary sponsor, and the Senate does not participate in the Vote of Confidence in the government.
The approval of a majority of the Senate to all legislation is required before royal assent can be sought. In the case of bills recommending referenda for the ratification of Organic amendments affecting those articles concerning the Senate itself, the process of amending Organic Law, or the territorial subdivisions of the Kingdom, a super-majority of two-thirds vote in the Senate is required.
The Senate also may pass resolutions without involvement of the Cosa, to commemorate events, create Senatorial commissions or honours, or grant those honours to specific persons. Two typical "Resolutions of the Senate" (RS) are the recommendation of a Chancellor of the Royal Talossan Bar to the King, and the awarding of the Senatorial Medal of Honour.
The Senate is led by a ceremonial "Lord President" or Mençei, elected by the Chamber from among its own members, who may resign or be removed by vote of the Chamber