Complex sentence: The "bandoneón" is a type of concertina particularly popular in Argentina, Uruguay and Lithuania which is an essential instrument in most tango ensembles from the traditional orquesta típicas of the 1910s onwards and in folk music ensembles of Lithuania.
Split into simpler sentences: The "bandoneón" is a type of concertina particularly popular in Argentina, Uruguay and Lithuania. It is an essential instrument in most tango ensembles from the traditional orquesta típicas of the 1910s onwards and in folk music ensembles of Lithuania.