Sangre (Spanish for “blood”) comes from the Latin sanguis for the same.
From that root, we also get.… sangria. Yes, the classic alcoholic wine plus fruit drink looks a bit like blood!
We also get a bunch of less common words, such as, consanguine (cousin marriages!) and even just sanguine, which originally meant “bloodthirsty”. It’s only a small step from the intensity of bloodthirsty to the cheery optimism of sanguine!