Final answer:
The Decree of April 6, 1830, was integral to the Texas Revolution as it aimed to stop American immigration, a factor which exacerbated tensions and contributed to the settlers' quest for independence.
Step-by-step explanation:
The Decree of April 6, 1830, is considered an important link in the chain of events leading to the Texas Revolution primarily because it stopped immigration from the United States. This decree was a measure taken by the Mexican government in response to the growing number of American settlers in Texas and their general disregard for Mexican laws, particularly those regarding slavery.
The decree not only halted American immigration but also increased Mexican military presence in Texas and offered land grants to promote Mexican and European settlement, in an effort to dilute the influence of American settlers. These efforts, however, did little to stem the tide of illegal immigration or to quell the desire for independence among the Anglo-American population, which continued to increase despite the restrictions.
The dissatisfaction culminated in the Texas Revolution, and the decree is seen as a catalyst for the ensuing conflict as it heightened tensions and pushed the settlers towards seeking independence.