He was born in Gengenbach in the Black Forest into a middle-class family - his father was army officer Johannes Casper Bender, son of Johannes Bender and Anne Marie Hetzler from Villingen, whilst Blasius' mother was Marie Eva Leutgardis Jüngling, daughter of Columban Jüngling and Anne Marguerite Bach from Ehrstein.

[3] In 1782 Joseph II, Holy Roman Emperor ennobled him and his four nephews as barons of the Holy Roman Empire and from 1783 onwards he lived in a new hôtel facing the Parc de Bruxelles - he had had it designed in the neoclassical style and it consisted of his residence and two separate houses.

It was remodelled for William I of the Netherlands to designs by Ghislain-Joseph Henry in 1818, twenty years after Bender's death, adding an arcaded gallery linking it to the hôtel de Belgiojoso and thus forming the nucleus of the future Royal Palace of Brussels.

In 1790 he was made a field marshal, his final rank, and in November that year he set out from Luxembourg to Brussels with 30,000 men.

[5] He managed to recapture Brussels from the rebels, before pacifying the whole Austrian Netherlands in a few weeks, allowing governor-general Albert Casimir, Duke of Teschen to resume his role.