Sons of the Basque educated classes went to Britain to complete their studies in civil engineering and commerce. While in the United Kingdom these students developed an interest in football and on their return to Bilbao they began to arrange games with British workers. In 1898 students belonging to the Gymnasium Zamacois founded the Athletic Club, using the English spelling.
In 1941, the club changed its name to Atlético Bilbao, following a decree issued by Franco, banning the use of non-Spanish language names and scrapping the policy of only letting Basque-born players in the team (see origins of the "grandparent rule").
In December 1975, before a game against Real Sociedad, Iribar and the Real captain Ignacio Kortabarria, carried out the Ikurriña, the Basque flag and placed it ceremonially on the centre-circle. This was the first public display of the flag since the death of Francisco Franco.