Bacterial leaf streak (BLS) is a disease of monocot plants caused by Xanthomonas translucens on small grains, X. vasicola on maize and sorghum, and X. oryzae on rice. BLS is becoming an increasing issue across the three pathosystems. BLS of barley is a major concern for barley producers globally. There is no available single gene resistance to X. translucens for breeders and multiple countries have imposed zero tolerance policies for X. translucens for the importation of barley grain from the U.S.A. Despite this concern, the diversity and distribution of clades of this pathogen on a global scale are not well understood. For effective germplasm screening, it is crucial to select a panel of strains which represent pathogen diversity. Long-read genome sequencing provides in-depth information about pathogen gene content. We completed PacBio sequencing of two modern Minnesotan X. translucens strains, commonly used in resistance screening, and completed in-depth analysis of available X. translucens long-read sequences from across the globe. Average nucleotide identity (ANI)-based approaches organize barley-infecting X. translucens into three LINgroups. Interestingly, the main clades according to ANI are present in both the Middle East and North America. We found a high degree of conservation of multiple effectors, such as 17 Type III-secreted effectors, which offer hope as potential elicitors of broad-spectrum resistance. However, we identified variation in the presence and absence of some virulence factors. Therefore, multiple X. translucens strains should be used to confirm resistance in barley lines. We further investigated similarity of effector content across all three BLS-causing species. However, we found that BLS pathogenesis likely convergently evolved via distinct mechanisms rather than from acquisition of conserved effectors.