Simon Stevin

He was a 17th-century Flemish mathematician and engineer. Some interesting bits from the Wikipedia article:

His claims to fame are varied. His contemporaries were most struck by his invention of a so-called land yacht, a carriage with sails, of which a little model had been preserved in Scheveningen until 1802. The carriage itself had been lost long before. Around the year 1600 Stevin, with Prince Maurice of Orange and twenty-six others, made use of it on the beach between Scheveningen and Petten. The carriage was propelled solely by the force of wind, and acquired a speed which exceeded that of horses.

And

Stevin thought the Dutch language to be excellent for scientific writing, and he translated many of the mathematical terms to Dutch. As a result, Dutch is one of the few Western European languages that have a lot of mathematical terms that do not stem from Latin. This includes the very name Wiskunde (Mathematics).