I got the feeling you were probably not a native English speaker and probably use another language at work. Even if you were working in an English-speaking country, that is in no way an excuse to take advantage of you and not pay you what was promised. Don't pay attention to the comment saying otherwise.

I am in a Spansh-speaking country, but am a native English speaker. It wouldn't be right for my boss to treat me the way he did because of that either. Although in my case, my ex boss was equal opportunity when taking advantage of people. The woman he owes money to and the one he keeps changing the pay terms with are both from here.

Although, he did frequently take advantage of one guy from Venezuela worse than most. He needed to show income to get his permanent residency visa, and he clearly didn't want to go back to Venezuela with all the problems there. Our boss would pile up a lot of extra work on him, things not in his job description, knowing it would be hard for him to say no, since losing his job would hurt his visa application. The poor guy would call me at 7:30 or 8 PM with work questions. He was still at the office working at that time! I heard his visa came through, so he was able to quit and now has a better job.