Sukarno was first exposed to nationalist ideas while living under Oemar Said Tjokroaminoto.
Later, while a student in Bandung, he immersed himself in European, American, Nationalist, communist, and religious political philosophy, eventually developing his own political ideology of Indonesian-style socialist self-sufficiency.
He began styling his ideas as Marhaenism, named after Marhaen, an Indonesian peasant he met in southern Bandung area, who owned his little plot of land and worked on it himself, producing sufficient income to support his family.
In university, Sukarno began organising a study club for Indonesian students, the Algemeene Studieclub, in opposition to the established student clubs dominated by Dutch students.

On 4 July 1927, Sukarno with his friends from the Algemeene Studieclub established a pro-independence party, the Indonesian National Party (PNI), of which Sukarno was elected the first leader.
The party advocated independence for Indonesia, and opposed imperialism and capitalism because it opined that both systems worsened the life of Indonesian people.
The party also advocated secularism and unity amongst the many different ethnicities in the Dutch East Indies, to establish a united Indonesia.
Sukarno also hoped that Japan would commence a war against the western powers and that Java could then gain its independence with Japan's aid.
Coming soon after the disintegration of Sarekat Islam in the early 1920s and the crushing of the Indonesian Communist Party after its failed rebellion of 1926, the PNI began to attract a large number of followers, particularly among the new university-educated youths eager for broader freedoms and opportunities denied to them in the racist and constrictive political system of Dutch colonialism.

PNI activities came to the attention of the colonial government, and Sukarno's speeches and meetings were often infiltrated and disrupted by agents of the colonial secret police (Politieke Inlichtingen Dienst/PID).
Eventually, Sukarno and other key PNI leaders were arrested on 29 December 1929 by Dutch colonial authorities in a series of raids throughout Java.
Sukarno himself was arrested while on a visit to Yogyakarta.
During his trial at the Bandung Landraad courthouse from August to December 1930, Sukarno made a series of long political speeches attacking colonialism and imperialism, titled Indonesia Menggoegat (Indonesia Accuses).

In December 1930, Sukarno was sentenced to four years in prison, which were served in Sukamiskin prison in Bandung.
His speech, however, received extensive coverage by the press, and due to strong pressure from the liberal elements in both Netherlands and Dutch East Indies, Sukarno was released early on 31 December 1931.
By this time, he had become a popular hero widely known throughout Indonesia.

However, during his imprisonment, the PNI had been splintered by the oppression of colonial authorities and internal dissension.
The original PNI was disbanded by the Dutch, and its former members formed two different parties; the Indonesia Party (Partindo) under Sukarno's associate Sartono who were promoting mass agitation, and the Indonesian Nationalist Education (New PNI) under Mohammad Hatta and Soetan Sjahrir, two nationalists who recently returned from studies in the Netherlands, and who were promoting a long-term strategy of providing modern education to the uneducated Indonesian populace to develop an intellectual elite able to offer effective resistance to Dutch rule.
After attempting to reconcile the two parties to establish one united nationalist front, Sukarno chose to become the head of Partindo on 28 July 1932.
Partindo had maintained its alignment with Sukarno's own strategy of immediate mass agitation, and Sukarno disagreed with Hatta's long-term cadre-based struggle.
Hatta himself believed Indonesian independence would not occur within his lifetime, while Sukarno believed Hatta's strategy ignored the fact that politics can only make real changes through formation and utilisation of force (machtsvorming en machtsaanwending).

During this pe
Sukarno was first exposed to nationalist ideas while living under Oemar Said Tjokroaminoto. Later, while a student in Bandung, he immersed himself in European, American, Nationalist, communist, and religious political philosophy, eventually developing his own political ideology of Indonesian-style socialist self-sufficiency. He began styling his ideas as Marhaenism, named after Marhaen, an Indonesian peasant he met in southern Bandung area, who owned his little plot of land and worked on it himself, producing sufficient income to support his family. In university, Sukarno began organising a study club for Indonesian students, the Algemeene Studieclub, in opposition to the established student clubs dominated by Dutch students.
On 4 July 1927, Sukarno with his friends from the Algemeene Studieclub established a pro-independence party, the Indonesian National Party (PNI), of which Sukarno was elected the first leader. The party advocated independence for Indonesia, and opposed imperialism and capitalism because it opined that both systems worsened the life of Indonesian people. The party also advocated secularism and unity amongst the many different ethnicities in the Dutch East Indies, to establish a united Indonesia. Sukarno also hoped that Japan would commence a war against the western powers and that Java could then gain its independence with Japan's aid. Coming soon after the disintegration of Sarekat Islam in the early 1920s and the crushing of the Indonesian Communist Party after its failed rebellion of 1926, the PNI began to attract a large number of followers, particularly among the new university-educated youths eager for broader freedoms and opportunities denied to them in the racist and constrictive political system of Dutch colonialism.
PNI activities came to the attention of the colonial government, and Sukarno's speeches and meetings were often infiltrated and disrupted by agents of the colonial secret police (Politieke Inlichtingen Dienst/PID). Eventually, Sukarno and other key PNI leaders were arrested on 29 December 1929 by Dutch colonial authorities in a series of raids throughout Java. Sukarno himself was arrested while on a visit to Yogyakarta. During his trial at the Bandung Landraad courthouse from August to December 1930, Sukarno made a series of long political speeches attacking colonialism and imperialism, titled Indonesia Menggoegat (Indonesia Accuses).
In December 1930, Sukarno was sentenced to four years in prison, which were served in Sukamiskin prison in Bandung. His speech, however, received extensive coverage by the press, and due to strong pressure from the liberal elements in both Netherlands and Dutch East Indies, Sukarno was released early on 31 December 1931. By this time, he had become a popular hero widely known throughout Indonesia.
However, during his imprisonment, the PNI had been splintered by the oppression of colonial authorities and internal dissension. The original PNI was disbanded by the Dutch, and its former members formed two different parties; the Indonesia Party (Partindo) under Sukarno's associate Sartono who were promoting mass agitation, and the Indonesian Nationalist Education (New PNI) under Mohammad Hatta and Soetan Sjahrir, two nationalists who recently returned from studies in the Netherlands, and who were promoting a long-term strategy of providing modern education to the uneducated Indonesian populace to develop an intellectual elite able to offer effective resistance to Dutch rule. After attempting to reconcile the two parties to establish one united nationalist front, Sukarno chose to become the head of Partindo on 28 July 1932. Partindo had maintained its alignment with Sukarno's own strategy of immediate mass agitation, and Sukarno disagreed with Hatta's long-term cadre-based struggle. Hatta himself believed Indonesian independence would not occur within his lifetime, while Sukarno believed Hatta's strategy ignored the fact that politics can only make real changes through formation and utilisation of force (machtsvorming en machtsaanwending).
During this pe
Sukarno