It is bad luck for a black cat to cross your path
Never turn your back on a black cat or you will be cursed
A black cat on the bed of an ill person will bring death
It comes down to the historical superstitions of Puritan Pilgrims of Plymouth Colony. This particular group of people lived by a strict Protestant lifestyle, shunning anything that went against their religious beliefs. Since witchcraft was viewed as a practice that worshiped the devil, the Puritans became extremely wary of everything that could possibly be linked to a witch.
Black cats were high up on that list. Legend had it that witches could transform into a black cat and back, emphasizing superstitions of these furry creatures. Some people even believed that witches could re-incarnate into black cats after death. Additionally, there was the Middle Age legend that the devil often gifted black cats to witches to act as their servants.
The naturally standoffish, stealthy attitude of cats probably didn’t help these felines, either. Paired with their dark fur coats and glowing eyes, black cats were feared as much as the human witches themselves. And as literature about witchcraft became more widespread, a period of “witchcraft hysteria” reigned between 1560 and 1660 in Europe and the New England colonies.
These days, many black cat superstitions still exist. They are often linked to bad luck and are feared by some. Just take a look at television shows, movies, and books; it's not uncommon to see a black cat portrayed in a spooky and tense environment.
So how does this all relate to Halloween? The basis of this modern holiday revolves around all things dark and spiritual. Many of the celebrations that take place during this time of the year focus on honoring the dead. Ancient traditions usually have some kind of link to either the practice of witchcraft or the opposing beliefs against them.
As a result, witches – and their black cats – have become a commercialized symbol of Halloween.