Johannes Jacobus (Hans) Ras (1 April 1926 – 22 October 2003) was emeritus professor of Javanese language and literature at Leiden University, the Netherlands. In 1961 he was lecturer at the University of Malaya, and in 1969 first representative in Jakarta of the KITLV (the Leiden-based Koninklijk Instituut voor Taal-, Land- en Volkenkunde = Royal Institute of Linguistics and Anthropology). Until his retirement he was several times a member of the board of the KITLV. From 1985 to 1992, he was professor of Javanese language and literature at the University of Leiden.
Hans Ras was born in 1926 in Rotterdam, the Netherlands, as the third son of a family of four children. His father had a wholesale business in confectionery, and all the children had to help in the business. They were all supposed to go to junior high school for their secondary education, as was usual at the time. However, when the eldest was expelled from such a school for precociousness and sent to a higher-grade high school, the others followed in his footsteps.
After Hans Ras passed his school-leaving exams, the Second World War broke out and he went into hiding, while his brothers were sent off into forced labour in Germany. Even at that time he was interested in languages, in particular the Javanese and Arabic language. But his high school certificate did not give him admission to an arts course at a university.
In 1946, Ras enrolled for the special course of Indonesian studies for future employees with the Dutch colonial civil service. However, the political developments in the then Dutch East Indies made him realize that there was no future for Dutch civil servants in that country. After switching to economics for a while, he left the Netherlands for France, where he found a job on a dam construction project. Here his knowledge of Arabic, acquired in his Indonesian studies course, stood him in good stead, as most of the workers were North Africans. He acquired a taste for travelling and travelled on to Libya, Egypt and Aden. On his return to the Netherlands, he did his national service training and after that, at the age of 24, applied for a job with the Rotterdam firm of Internatio (now called Internatio-Müller). He was sent to Indonesia, where he worked in then Batavia. Later he was sent as representative to Banjarmasin, in Southeast Kalimantan, to buy rubber from local growers. This was not without its dangers in the precarious relations between the Netherlands and Indonesia in those years. The local leftist trade unions were hostile to colonial capital, of which they regarded Internatio as a typical representative. In some of the violent demonstrations Ras was repeatedly threatened personally. For instance, once some workers who had been sacked used traditional medicine men to cast a spell on his house. As it became impossible to do his work here any longer, he returned to the Netherlands.