By the spring of 1824 Milam returned to Mexico, which now had adopted the Constitution of 1824 and had a republican form of government. In Mexico City he met Arthur G. Wavell, an Englishman who had become a general in the Mexican army. Trespalacios, now prominent in the new government also, made overtures to Milam to renew their friendship, and Milam accepted. He was granted Mexican citizenship and commissioned a colonel in the Mexican army in 1824. In 1825-26 he became Wavell's partner in a silver mine in Nuevo León; the two also obtained empresario grants in Texas. Wavell managed the mining in Mexico and leased the most productive mine to an English company, which by 1828 was unable to fulfill the terms of their contract. In 1829 Milam sought to organize a new mining company in partnership with David G. Burnet, but they were unable to raise the necessary capital.
In April 1830 the Mexican Congress passed a law prohibiting further immigration of United States citizens into Texas. This was one reason why Milam, as Wavell's agent for his Red River colony, and Robert M. Williamson, as agent for Milam's colony, were not able to introduce the required number of settlers specified in their empresario contracts, which were due to expire in 1832. During this time Milam removed the great Red River raft of debris, which for years had blocked traffic in the upper part of the Red River for all vessels except canoes and small, flat-bottomed boats. He then purchased a steamboat, the Alps, the first of its kind to pass through the channel.
In 1835 Milam went to Monclova, the capital of Coahuila and Texas, to urge the new governor, Agustín Viesca, to send a land commissioner to Texas to provide the settlers with land titles. Viesca agreed to do this. However, before Milam could leave the city, word came that Antonio López de Santa Anna had overthrown the representative government of Mexico, had established a dictatorship, and was en route to Texas with an army. Viesca fled with Milam, but both were captured and imprisoned at Monterrey. Milam eventually escaped and headed for the Texas border, which he reached in October 1835. By accident he encountered a company of soldiers commanded by George Collinsworth, from whom he heard of the movement in Texas for independence. Milam joined them, helped capture Goliad, and then marched with them to join the main army to capture San Antonio. While returning from a scouting mission in the southwest on December 4, 1835, Milam learned that a majority of the army had decided not to attack San Antonio as planned but to go into winter quarters. Convinced that this decision would be a disaster for the cause of independence, Milam then made his famous, impassioned plea: "Who will go with old Ben Milam into San Antonio?" Three hundred volunteered, and the attack, which began at dawn on December 5, ended on December 9 with the surrender of Gen. Martín Perfecto de Cos and the Mexican army. Milam did not survive to witness the victory, however. On December 7 he was shot in the head by a sniper and died instantly. In 1897 the Daughters of the Republic of Texas erected a monument at Milam's gravesite in Milam Park, San Antonio. The marker was moved in 1976, and the location of the grave was forgotten until 1993, when a burial was unearthed that archeologists think is probably Milam's. Source
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