Antimicrobial resistantSalmonella entericaserovar Concord (S. Concord) is known to cause severe gastrointestinal and bloodstream infections in patients from Ethiopia and Ethiopian adoptees, and occasional records exist ofS. Concord linked to other countries. The evolution and geographical distribution ofS. Concord remained unclear. Here, we provide a genomic overview of the population structure and antimicrobial resistance (AMR) ofS. Concord by analysing genomes from 284 historical and contemporary isolates obtained between 1944 and 2022 across the globe. We demonstrate thatS. Concord is a polyphyletic serovar distributed among threeSalmonellasuper-lineages. Super-lineage A is composed of eightS. Concord lineages, of which four are associated with multiple countries and low levels of AMR. Other lineages are restricted to Ethiopia and horizontally acquired resistance to most antimicrobials used for treating invasiveSalmonellainfections in low- and middle-income countries. By reconstructing complete genomes for 10 representative strains, we demonstrate the presence of AMR markers integrated in structurally diverse IncHI2 and IncA/C2 plasmids, and/or the chromosome. Molecular surveillance of pathogens such asS. Concord supports the understanding of AMR and the multi-sector response to the global AMR threat. This study provides a comprehensive baseline data set essential for future molecular surveillance.