Chevaux de Frise
(French). Horses of Friesland. A beam filled with spikes to keep off horses, so called from its use in the siege of Groningen, Friesland, in 1594. A somewhat similar engine had been used before, but was not called by the same name. In German it is “a Spanish horseman” (ein Spanischer Reiter).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894