Please help me create a cast for the Alamo?

My teacher gave us a project and one part of it is creating a cast of charecters just like if we want to make a movie about the Alamo. He said that we have to select famous actors. He says that you have to pick a actor/actress that fits the person he or she is playing, for example, we couldn't choose a white person to play Santa Anna. Also, the personalities of the actor and the person that he plays have to be simmilar. Supposely we can't pick actors that did the "The Alamo" movies. I have no idea how to do this project. Please help me the best you can. Try to follow the tips mentioned above for me, but if you can't, I think it'll be alright if you break just a few rules. Thanks a ton. The mandentory charecters are Colonel Travis, Bowie, Santa Anna, and Crockett. Optional (extra credit) charecters are Juan Seguin, Susanna inson