Final answer:
General Antonio Lopez de Santa Anna's rise to power in Mexico led to conflict with American settlers primarily because of his centralization of government and the dissolution of Congress through the Siete Leyes (Seven Laws).
Step-by-step explanation:
General Antonio Lopez de Santa Anna's rise to power in Mexico led to conflict with American settlers primarily because of his centralization of government and the dissolution of Congress through the Siete Leyes (Seven Laws). This centralization of power alienated the American settlers who were used to separation of powers and a more decentralized government structure. As a result, the Americans in Texas revolted and declared independence from Mexico, leading to the Texas Revolution and eventually the Mexican-American War.