The post-independence period was tumultuous, with many military coups and coup attempts shaking the country from 1949 to 1971. In 1958, Syria entered a brief union with Egypt called the United Arab Republic, which was terminated by the 1961 Syrian coup d'état. The republic was renamed as the Arab Republic of Syria in late 1961 after the December 1 constitutional referendum of that year, and was increasingly unstable until the 1963 Ba'athist coup d'état, since which the Ba'ath Party has maintained its power. Syria was under Emergency Law from 1963 to 2011, effectively suspending most constitutional protections for citizens.