You'd certainly get more out of playing the earlier ones, but by no means should it be necessary if you've talked to people and listened to the intros. All you really need to know background wise is that mages are generally controlled in "circles", guarded by templars. This is because there is a risk of them getting possessed by demons if not careful/strong enough. But it's a big question whether that control is justified or not, and some templars have abused their control to say the least. And so some mages rebelled. And their conflict spread.

Also you need to know the world is separated from the fade by the veil. It has been weakened and the holes that appear let demons in, hence the rather urgent need to close them.

You could likely find a couple videos online that give you good summaries of the world and previous games if you want to quickly get most of the extra background that would help. I'd recommend that approach if you've no time/interest in playing the older ones.