Calls for a National Assembly were part of the platform of the revolutionaries who overthrew the Qing dynasty. In 1947, the Kuomintang promulgated a constitution and the 1st National Assembly session met in the Chinese capital Nanjing. Shortly afterwards in 1949, the Mainland fell to the Communists and the National Assembly (along with the entire ROC government) was transplanted to Taiwan.
The 1947 National Assembly was to have been elected for a period of seven years however the fall of the Mainland made it impossible to hold new elections. As a result, the Judicial Yuan decided that the members of the National Assembly would continue to hold office until new elections could be held on the Mainland.
As a result of this decision, the same National Assembly remained until 1991, when as part of constitutional settlement a Second National Assembly was elected.
After the passage of the Constitutional reforms, there was strong objection to what was essentially a permanent constitutional convention. Because of this, in 1997 the National Assembly was suspended and will only be called into session if a constitutional amendment is considered.
Originally, the National Assembly elected the President and Vice President of the Republic of China. A subsequent constitutional amendment abolished this role and established direct popular elections. Additional amendments have delegated any impeachment legislative functions to the Legislative Yuan.
Despite being suspended, the National Assembly still has a constitutional role. The main argument against its abolition is that they only way then to amend the ROC Constitution would be to hold a popular referendum on Taiwan, and this would sharply reduce the threshold necessary to declare Taiwan independence.