for what was this draft signed?
For the purchase included lands south of the Gila River and west of the Rio Grande.
Gadsden Purchase
 The purchase included lands south of the Gila River and west of the Rio Grande where the U.S. wanted to build a transcontinental railroad along a deep southern route, which the Southern Pacific Railroad later completed in 1881–1883. The purchase also aimed to resolve other border issues.

who negotiated the purchase of the area south of gila river UNANSWERABLE what do you mean by this purchase? It is a region of present-day southern Arizona and southwestern New Mexico. is there any person after whom this area is named? James Gadsden who was this person? An American diplomat, soldier and businessman. why is the above place related to him? The first draft was signed on December 30, 1853, by him.
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Gadsden Purchase [SEP] Introduction
After the devastating loss of Mexican territory to the U.S. in the Mexican–American War (1846–48) and the continued filibustering made by New Mexico governor William Carr Lane in the zone, Santa Anna may have calculated it was better to yield territory by treaty and receive payment rather than have the territory simply seized by the U.S.