Final answer:
Austin was able to bring more than 1,200 settlers to Texas due to the Mexican government's invitation and their favorable land terms. Thousands of American settlers, mainly from slave states, were attracted to Texas due to the opportunities for expanding slavery and the cotton kingdom.
Step-by-step explanation:
The Mexican government's invitation allowed Austin to bring more than 1,200 settlers to Texas. Mexico wanted to encourage settlement in the region and passed colonization laws to attract immigrants. Unlike the U.S. government, Mexico offered favorable land terms and allowed buyers to pay in installments. This attracted thousands of American settlers, primarily from slave states, who saw the soil and climate of Texas as opportunities for expanding slavery and the cotton kingdom.