My boyfriend is a Mexican citizen who was in the US illegally when we met. He has since returned to Mexico because of his mother's health. When he was in the states, he married a Mexican American but decided he'd rather run the risk of being deported than having to live with her and did not complete the requirements to become a resident. As I stated above, he did return to Mexico on his on free will. I have visited him there and we are contemplating marriage. If we decide to do this, what is best way to do this so that he can return to the states legally so that we can be together? I do realize that he will have to be divorced first. Should I go to Mexico to marry him? Should we go the Fiance' Visa route? What would the time frames be for both for him to be able to return to the states legally?

Just getting married is no promise of becoming a citizen. He will need to start his immigration process legally

When does he begin this paperwork? Would he be able to come by to the states as just a resident?