Which law governed individual relationships and defined legal rights in Texas before January 20, 1840?

The law that governed individual relationships and defined legal rights in Texas before January 20, 1840, was Spanish Law. During this period, Texas was still under Spanish influence, and the legal system was based on the civil law traditions brought by Spanish colonization. Spanish Law characterized relationships and legal rights concerning property, family, and contractual matters, offering a framework that reflected the cultural and social norms of the time.

Civil Law, while a valid choice in many contexts, refers more broadly to a body of laws rather than the specific legal system in place in Texas during that era. In contrast, Common Law, which developed primarily from English legal traditions, and Statute Law, which is based on written laws enacted by a legislative body, did not dominate Texas's legal landscape until later. Thus, Spanish Law is the most accurate answer, reflecting the legal context prior to the establishment of more modern legal frameworks in Texas.