The question above could be dissected as an exercise in itself but in the interest of sanity let us gloss over the meanings of 'historical' novels. Suffice it to say that a novel written about life before we were born, no matter how much before, is intrinsically historical.
I have read stories going back millennia. A story well-told is entertaining and surely that is one factor in why we read, the other is for education. By that I mean for information purposes. In the case of stories like Wolf Hall by Hilary Mantel the skill of the writer is to convey the idea of what life was really like in the 16th century. It is the creative cloak wrapped around verifiable historical facts and can be made engaging as well as challenging. Hilary Mantel did that very well.
Going back to the original question I would suggest that a majority of us will read a historical story at some time in our lives. Some of those stories may be of relatively recent history such as the 20th century wars that generates many books both fact and fiction. Others may be from further away in history as in Bernard Cornwell's Sharpe series. Whatever your personal preference there seems to be something for almost everyone in this genre.
The very first historical novel I read was I Claudius by Robert Graves which I devoured while selling ice cream as a holiday job. It opened the door for me to consider other such novels.
My next historical adventure will be the Wolf of the Plains by Conn Iggulden a tale of 13th century Genghis Khan.
I have produced a blog on historical novels without mentioning the classics such as Wuthering Heights, Jane Eyre or Sense and Sensibility. Quite deliberate as we are all familiar with that leg of the genre. Lots to read.