Elektroton was founded in 1938 in the former Kingdom of Yugoslavia.
At first this was a small plant situated in Ljubljana .
In the same year its owner Josip Križanec decided to relocate the companies production to Zagreb,its production line increased to 60.000 records per year.
Mostly this were records produced on foreign manufacturing licence - english, german, spanish, french, american and italian "Slager-music", which certainly influenced the domestic music production but didn't directly effected its development.
Elektroton startet its own record-label production only in 1944.
After the II World War ended Elektroton was nationalized and on its grounds Jugoton Records was established in 1947. [Discogs]
The prolific Croatian inventor Slavoljub Penkala developed an early form of plastic, called ebonite, for use in the production of gramophone records. He contracted with the Edison-Bell company, England, and a new company Edison-Bell-Penkala Ltd. was founded in Zagreb. In 1908 Penkala and partner Edmund Moster molded their first gramophone records. (Penkala later went on to improve gramophone pickup and needle technology.) [Source]