Title VII of the Civil Rights act of 1964 prohibits discrimination based on sex, color, religion, and national (ethnic) origin. Other statutes prohibit discrimination based on age and disability. For Title VII to apply to your company, you must have 15 or more employees. For the Age Discrimination in Employment Act to apply, you must have 20 or more employees. Think about that. Thousands of employers are not covered by Title VII or the other discrimination statutes.
The intent was to avoid placing too great a burden on smaller employers, the "mom and pop" businesses out there who employ a huge percentage of workers. I am sure this employee limitation was intended as early tort reform. But, it also means some employers can discriminate based on factors most of us would not support.
If Title VII does not apply, then the "Reconstruction statutes," laws passed during Reconstruction in the 1870’s, might apply. 42 USC Sec. 1981 and 1983 apply regardless of the number of employees. These statutes protect racial and ethnic minorities from discrimination in the formation of contracts. Employment can be a type of contract. If you have a question, you should discuss your situation with an employment lawyer.