First, it’s not a regent, it’s a Regents Exam. There’s something called the Board of Regents, which I think is something like a board of trustees for the NYS education department. It’s named after them.
Regents Exams have been around for almost 150 years. At some point, I’m sure there was a one-year course on world history, but it’s been a two-year course for many years. You’re lucky that when you take the English Regents Exam, it will only be a one-day (3 hour) test. It was a 2-day (6 hour) test until recently.
I hope your writing on the essays is a lot more formal than your posts here.