Argentina , officially the Argentine Republic, is a federal republic
What do you mean by federal republic?
The Basic Law for the Federal Republic is the constitution 
What is Argentian's constitution called?
Not sure, but The adoption of the Constitution was preceded by a period of agitation
How long did the agitation last?
modern-day Argentina dates back to the Paleolithic period. The Inca Empire expanded to the northwest of the country in Pre-Columbian times. The country has its roots in Spanish colonization of the region during the 16th century. Argentina rose as the successor state of the Viceroyalty of the Río de la Plata, a Spanish overseas viceroyalty founded in 1776. The declaration and fight for independence (1810–1818) was followed by an extended civil war that lasted until 1861, culminating in the country's reorganization as a federation of provinces with
that preceded it. The German state's official name was "Deutsches Reich" until the adoption of the 1949 Basic Law.
Origin.
Following the end of World War I, a German National Assembly gathered in the town of Weimar, in the state of Thuringia, after the 19 January 1919 Federal elections, in order to write a constitution for the "Reich". The nation was to be a democratic federal republic, governed by a president and parliament.
The constitution was drafted by the lawyer and liberal