Yapto Soerjosoemarno, born on December 16, 1949, in Surakarta, is an Indonesian political and social figure. He is primarily known for being the long-time leader of the nationalist paramilitary organization Pemuda Pancasila (Pancasila Youth), which he has led continuously since 1981. His career is inextricably linked to the leadership of this group, which under his command has maintained a significant influence in Indonesian politics and society, promoting a nationalist and anti-communist ideology. In addition to his role in Pemuda Pancasila, Soerjosoemarno founded the Patriot Party (Partai Patriot) in 2001, an effort to translate his power base into a formal political vehicle. Although a controversial figure, he is widely recognized as one of the most powerful and long-serving leaders of mass organizations in Indonesia, exerting his influence in both business and politics.