His father came to Brunant in the 1380s to work for the Venetians as a tax collector. Fredrick was born in Donderstad. Van der Haas assisted his father as an accountant but by 1423 became a moneylender. He was involved in financially aiding the Dutch during the War of Independence.
In 1427 he attended the Convention of Grijzestad and was a signatory of the Declaration of Independence. In 1436 he was accused of strealing money and charging high interest rates and was imprisoned at the infamous Zwartstoren. When he finally was released in 1440 he was not allowed to constinue as a moneylender. But in 1445 he was arrested again; it was found that he had adopted the name Adriaan Muller and continued to operate illegally. He remained in prison until his death in 1461.