I recently met someone who used this in the following way:
…you know I want to keep a good relationship with them. I told them I don't want any bad blood between us.
I'd never heard this before, but I understood it contextually, and I know what it means now.
The American Heritage Dictionary of Idioms dates the expression bad blood to the early 19th century:
This term is based on the old association with blood and emotion, particularly anger. Versions such as ill blood preceded it; Charles Lamb was among the first to use the idiom in its current form in an 1823 essay.
But Merriam-Webster dates its usage much earlier:
First Known Use of bad blood
1664
Can anyone help clarify its origin and date its earliest usages?
Best Answer
From what I researched: Dictionary.com states that the phrase "bad blood" was first recorded 1815 to 1825, and this seems to be the most accepted time from when I cross-referenced this.
Dictionary.com
However, there are people who can give examples from even earlier than this. Therefore, I think Merriam-Webster is correct, or quite close. Check out this link to a discussion I found.
Word Wizard
Hope this helps!