19 January 1977,
[Legalization of ikurrina in Hego Euskal Herria]. Just a month earlier, the Law on Political Reform was passed in the Spanish state, initiating the so-called Transition. In Hego Euskal Herria, the ikurrina movement was widespread. ETA also conducted a specific campaign in this area. During the celebration of the Ikurrina it settled in numerous municipalities.
Source:
Gotzon Aranburu (Naiz, 19 January 2017).