In an attempt to keep unity within the Soviet Union, the country held a referendum on 16 March 1991 and Kazakhstan voted 95% in favor of a new Union of Sovereign States. After the aborted coup d'état in August, the Supreme Soviet (Kazakhstan) passed the "Constitutional Independence Law of Republic of Kazakhstan" on 16 December 1991. Despite the swift collapse of the Soviet Union, Kazakhstan was the last to declare its independence. The declaration was followed up by the Alma-Ata Protocol which would give birth to the Commonwealth of Independent States. Independence ushered in the era of President Nursultan Nazarbayev, during which a new two house parliamentary system and a new capital was established. Notable events that followed as an indirect result of independence include: