Complex sentence: After defeating a Mexican expedition against San Antonio in 1842 the Mexican commander devised a plan to put anglo Texans against Seguin by publicly stating that Seguin was still a loyal Mexican subject.
Split into simpler sentences: After defeating a Mexican expedition against San Antonio in 1842 the Mexican commander devised a plan to put anglo Texans against Seguin. The Mexican commander stated publicly that Seguin was still a loyal Mexican subject.