The character of Quentin Collins was created at the request of Jonathan Frid, who asked that a second villain be brought in to lighten his workload.
For more than a year and a half, the characters of this show used almost every possible phrase to refer to Barnabas Collins ("He's not alive!", "He's one of the undead.", "He walks at night, but he ain't alive.") It wasn't until the 410th episode that the word "vampire" was used on the show.
Originally, David Selby donned fake sideburns for the role of Quentin Collins, but eventually he grew his own, so he would no longer have to endure the make-up.
In an interview with writer Ron Sproat, he and fellow writer Gordon Russell had just met with the show's creator, Dan Curtis, where they were given the news that a vampire would be added to the show. After the meeting, the two writers were on an elevator and it was at that moment that they decided that Barnabas would be "a reluctant vampire" with a conscience. It was the right decision, as Barnabas saved the show from the axe. They kept him on as the lead when he was only supposed to be around for a few episodes. This incidentally made Barnabas Collins the first example of a sympathetic vampire seen on-screen.
The producers planned to run the 1897 storyline for three months, but it was so popular that they ended up expanding it to eight and a half months.