Immediately following the party's formation a period of intense activity began, especially amongst the Greek youth. Within six months of the party's formation it had established offices in 14 cities and combatant cells in even more cities. On 1 August 1965 the first issue of the party's bi-monthly newspaper "4th of August" was published under Dimopoulos as its editor. While the party's offices continued to expand to other areas of Greece the city of Thessaloniki stood out as a strong power base, particularly among university students. The party's youth movement, Student National Vanguard, dominated the 1966 student elections of the University of Thessaloniki. By 1967 the party was publishing literature, holding events, and creating organizations to work in conjunction with the party. Aside from the Student National Vanguard, these also included Scholastic Nationalist Movement, Union of Friends of the 4th of August Party, and a trade union. It is notable that prefects and mayors were counted among the ranks of the Union of Friends of the 4th of August. The party also had a close relationship with Konstantinos Maniadakis, a personal friend and confidant of Ioannis Metaxas as well as the Minister of Security of the 4th of August government.
Post-junta period and the end of the party
After the collapse of the junta, Plevris and all of the other imprisoned 4th of August Party members were initially released in July as part of the general amnesty. The 4th of August Party was then reinstated in its second organizational phase and attempted to continue its pre-junta activities. However, the new liberal democratic regime of Karamanlis not only continued but intensified the political persecution of the 4th of August Party that had begun during the junta period. During this period, there were allegations of state-sponsored persecution against 4th of August Party members which included police illegally entering and searching their homes, allegedly groundlessly arresting them, police allegedly overlooking para-state terrorism directed against the 4th of August Party, alleged police frame-ups of members of the party, and even alleged judicial bias directed against the party. In addition, Plevris and other leading figures of the party were arrested and detained; this led to the 12-year imprisonment of Aristotelis Kalentzis for terrorist activities ; Plevris himself was cleared, causing Kalentzis to launch a polemic against him, accusing him of being a para-state agent that framed him. Under such an atmosphere, the party could no longer function and a decision was made to suspend its activity in 1977. The final issue of the party's newspaper circulated in October of that year.
