Romania:
republic

Russia:
federation

Rwanda:
republic; presidential, multiparty system

Saint Helena:
NA

Saint Kitts and Nevis:
constitutional monarchy with
Westminster-style parliament

Saint Lucia:
Westminster-style parliamentary democracy

Saint Pierre and Miquelon:
NA

Saint Vincent and the Grenadines: parliamentary democracy; independent sovereign state within the Commonwealth

Samoa:
constitutional monarchy under native chief

San Marino:
independent republic