In late 1968, at the zenith of the movement, thousands of students entered Tokyo's busiest railway station, Shinjuku, and rioted.

The students drew ideological inspiration from the works of Marxist theorists like Karl Marx and Leon Trotsky, French existentialist philosophers like Jean-Paul Sartre and Albert Camus, and the homegrown philosophy of the Japanese poet and critic Takaaki Yoshimoto.

[9] The students' devotion to shutaisei in particular would lead ultimately to the disintegration of their movement, as they focused increasingly on "self-negation" (jiko hitei) and "self-criticism" (hansei).

The occupation authorities repealed the Peace Preservation Law, which had been enacted before the war to target left-wing groups specifically and arrest their members.

Left-wing groups supported the Constitution and students sought to protect it and defend themselves against actions by the Japanese state they viewed as unconstitutional.

[20] In 1960, a broad coalition of left-wing groups including the JCP, the JSP, Zengakuren, and the Sōhyō trade federation representing Japanese trade unions carried out massive protests against renewal of the Treaty of Mutual Cooperation and Security Between the United States and Japan (known commonly as Anpo).

[22] During the Anpo protests of 1960, a split occurred between two leading left-wing intellectuals – Masao Maruyama and Takaaki Yoshimoto.

Maruyama saw the protest as an example of the enacting of the concept of shutaisei (subjectivity), or the idea of the autonomy of society from the state and the self, and as a shining beacon of democratic ideals.

Yoshimoto accused Maruyama and his supporters of being duplicitous, hypocritical, and going against shutaisei by deceiving themselves into believing they were against the war and the heralds of popular democracy.

Zengakuren attacked the JCP, the progressives, and anything else they deemed as the "Establishment" as organizations that threatened shutaisei by destroying the autonomy of the self and replacing it with a vanguard.

The lack of post-war publication censorship,[10] the printing of affordable Marxist texts and the abundance of free time at university led to the radicalization of many more students.

As riot police were called in to protect these ceremonies, the students moved to occupy Yasuda Hall in June.

The University of Tokyo decided to take measures to take back Yasuda Hall from student occupation and clear its barricades.

[27] The Zenkyōtō brought the actions of non-sectarian activists –[note 2] people who did not follow any set path to revolution and were unaffiliated with either Zengakuren or the JCP – to light.

[39] In the same month, talks broke down, violence reemerged on campus, and the Zenkyōtō slowly lost control to different organizations.

In November, members of the Kakumaru-ha, a breakaway organization of the Trotskyist Japan Revolutionary Communist League, took nine professors as hostages, including Literature Faculty Dean Kentarō Hayashi.

These factions brought factionalist divisions onto campus, leading to fights where non-sectarian students intervened to either break them up or provide first aid.

An American jet crashed into the computer center at Kyushu University, sparking anti-American protests aimed at shutting down Brady Air Base.

Thousands of students entered Shinjuku Station on October 21 (International Anti-War Day)[45] and rioted,[46] leading the police to invoke the Riotous Assembly Crime Act.

[57] The explosion of student unrest following the Yasuda Hall siege led to the number of occupied campuses skyrocketing from 33 to 77 by March[57] and 111 by April.

[67] The National Zenkyōtō, formed in 1969, whose activity peaked in September with a rally held in Hibiya Park,[68] fractured from infighting.

[69] Despite the destruction of any unity between Zenkyōtō, students continued to riot in the streets, with more of their attention turned to concerns like the war in Vietnam and the upcoming renewal of the Anpo treaty.

[77] Minsei, as a more reformist faction aligned with the JCP, believed that compromise was possible with professors and that their ultimate opponent was the oppressive force of the Ministry of Education.

[80] The students wished to have a sense of personal self-hood or agency and wanted to join with other people looking for shutaisei to affirm this through fighting.

[81] Some of the most popular books within the student population of Japan at the time were existentialist works such as Dostoevsky's The Brothers Karamazov and Camus's The Stranger.

The waning influence, power and public image of the left, as well as increased police scrutiny, led to the failure of the 1970 Anpo protests.

This lack of understanding towards the self was one of the main inspirations for writer Haruki Murakami[87] – some of his books deal directly with the aftermath of the protests in the 1970s, like Hear the Wind Sing.

[88] Other famous books inspired by the protests include the 1977 Zenkyōtō novel Boku tte nani by Masahiro Mita (ja), and 69 by Ryū Murakami (further adapted into a 2004 film).

[90] Philosopher and semiotician Roland Barthes even dedicated a section of his book Empire of Signs to the Zengakuren students.

[96] The failure of female students to be treated equally during the protests led to a greater awareness among women of gender inequality on campus.