This uniquely-shaped pecan tree, on the west bank of the Medina River about twenty-five miles from San Antonio, marked the approximate location where Henry Castro and a small group of colonists camped on September 3, 1844. Eight days later Bishop John M. Odin, the first Catholic Bishop of Texas, said Mass in its shade and dedicated a cornerstone for the first Catholic church in the new colony.

Henry Castro was a Frenchman by birth and a Jew by faith, but he bore a Spanish name. He visited America as consul for the kingdom of Naples in 1827 and became an American citizen in that same year.

Castro was one of four men who were successful in obtaining a colonization contract from the Republic of Texas in 1841-42. From 1842 to 1844, Castro was responsible for introducing more than 2,100 immigrants to Texas. In addition to Castroville, he also founded colonies at Quihi, New Fountain, D'Hanis, and Vandenburg.

Castroville was the first permanent colony to be established between San Antonio and the Rio Grande.

Legal entanglements and delayed payments for services rendered as empresario of the colonies he established eventually cost Castro a personal fortune in excess of $100,000 and much of the land he received under his colonization contract. During the War Between the States, he decided to return to France, where he hoped to raise additional funds. His journey took him only as far as Monterrey, Mexico, where he died on November 3, 1865. His wife, Amelia Mathis, is interred in the Castroville cemetery beside their daughter-in-law, Augustine.

Castro's contribution to the settlement of Texas was recognized in 1876, when the Legislature created and named in his honor a county in the northwest part of the state.

The tree died after an unusually cold winter in 1985, but has been replaced by a young sapling raised from pecans from the original tree. An interpretive display has been constructed by Texas Parks & Wildlife Department.

The Castroville Pecan was located behind the Landmark Inn, in Castroville.