United States and Mexican Boundary Commission
The Joint United States and Mexican Boundary Commission was stipulated by the Treaty of Guadalupe Hidalgo which ended the Mexican–American War in 1848. The Joint Commission was required to carefully survey and mark the new boundary which had only been imprecisely described in the treaty between the two countries. Each country appointed a commissioner and a surveyor to jointly lead the project and the group met for the first time in San Diego on July 6, 1849. The survey was expected to take only a year, but the effort was poorly funded and  fraught with internal dissension and personnel turnover, especially within the American contingent. In addition, neither country had appreciated the extremely difficult terrain through which the survey would be conducted. The 1847 Dirsturnell map accompanied the Treaty of Guadalupe Hidalgo There were discrepancies in the map and in the Spring of 1851 the Commissioners negotiated the Bartlett-García Conde Compromise to end the dispute over where the southern border of New Mexico would be. The Compromise was rejected by the US Senate however, and a new boundary limit had to be negotiated. The Gadsden Purchase and negotiation determined that new boundary . John Russell Bartlett replaced John C. Frémont as the US Boundary Commissioner on June 15, 1850. The Mexican Commissioner was Pedro García Conde. List of US Boundary Commissioners List of US Boundary Surveyors List of Mexican Boundary Commissioners List of Mexican Surveyors