[5] All sources stress the influence of the African communities and their rhythms, while the instruments and techniques brought in by European immigrants played a major role in its final definition, relating it to the salon music styles to which Tango would contribute back at a later stage, when it became fashionable in early 20th century Paris.
[11] Initially tango was just one of the many dances practiced locally, but it soon became popular throughout society, as theatres and street barrel organs spread it from the suburbs to the working-class slums, which were packed with hundreds of thousands of European immigrants.
[15] Afro-Argentines and the other working-class populations were especially crucial in shaping the emergence of tango by combining the different influences, including the milonga, the condombe, and payada.
[16] Additionally, tango was also closely associated with brothels and bars of Buenos Aires, which the elites also considered disreputable.
In 1912, Juan "Pacho" Maglio was very popular with his recorded tangos featuring the bandoneon accompanied by flute, violin and guitar.
[11] By 1912, dancers and musicians from Buenos Aires travelled to Europe and the first European tango craze took place in Paris, soon followed by London, Berlin, and other capitals.
In 1916, Roberto Firpo, an extremely successful bandleader of the period, cemented the instrumentation for the standard tango sextet: two bandoneons, two violins, piano and double bass.
Firpo heard a march by Uruguayan Gerardo Matos Rodríguez and adapted it for tango, creating the popular and iconic La Cumparsita.
However, in 1921, 'El Sonido de la Milonga' helped bring about the rise of tango, and introduced it properly as a form to the people.
[18] In Argentina, the onset in 1929 of the Great Depression and restrictions introduced after the overthrow of the Hipólito Yrigoyen government in 1930 caused Tango to decline.
Its fortunes were reversed as tango became widely fashionable and a matter of national pride under the government of Juan Perón.