The multidisciplinary tax research has developed several understandings which could be inspirational for the historiography of the Belgian tax system. At the same time an historical approach to tax culture can open up relevant prospects for present-day policies. An analysis of determining factors of tax behaviour avails insight into the maturation of a tax culture and tax mentality. What are the difficulties and sensitivities the tax authorities have to deal with? Where do they originate? How can they be understood? The Belgians appear to consider tax fraud as a national sport. How can this be explained? This article maps the most significant concepts drawn from behavioural economics, psychology of taxes and fiscal sociology, and defines the idea of tax culture. Based on these understandings the 19th century Belgian tax culture is explored for the first time. The enquiry proves that current concepts in tax research can offer a whole new dimension to the fiscal historiography. It shows that determining factors of tax behaviour have a long tradition. Hence history can provide useful insight into tax policy. In order to reduce the tax gap authorities do not only benefit from an in-depth examination of the motives for tax compliance today, but should equally consider an historically developed tax culture.