Mexican migration to the u. s. has a long history. historical and current mexican immigration patterns have been influenced by:

Historically reasons were various, often including things like religious freedoms or economic freedoms or freedom from prosecution. Nowadays it's mostly economic as people go to the United States from Mexico in search of jobs and financial security, so that they could help their families in Mexico, or try to save money.

A. southerners underestimated republicans eagerness to end slavery.