According to Slate, the phrase m%therf*c%er (referring to someone who or something that is despicable) first came about in the "late 19th and early 20th centuries" and was originally documented during a "Texas Court of Appeals’ account." It was here that a witness referred to a defendant as a “G!d d@mned m#ther-f—ing, b@st@#%ly son-of-a-b—h.” Wow.
Then in World War II, the phrase became a more popular way to say someone or something is irritating or ruthless.
But, as the 1950s rolled around, the word "m%therf*c%er" took a turn for the good if you can believe it. It became used in a more favorable way to describe someone you're close with. For example, "I love him madly, he’s my m—erf—ng man," which was a line from the 1954 poetry book, The Life.