Continuity mistake: In an early scene Travis and Dickenson are in Travis's office. Travis goes to the mantel, gets a cigar and pours himself a glass of sherry. In a later scene, when Travis meets Crockett in the cantina he refuses a drink from Crockett claiming he doesn't drink, ever.
Continuity mistake: In the scene on the last assault on the Alamo, Mexican cavalry (in red coats) jump the palisade next to the chapel and are killed by a volley of musketry and their bodies are littered everywhere. Next time you see the area, however, the bodies have disappeared.
Continuity mistake: When Crockett's party first see San Antonio, they are carrying little more than blanket rolls on their horses - and no pack mules. However, when Crockett tells them to change into their best duds, top hats and other clothes appear from nowhere.